diff --git a/.repo-metadata.json b/.repo-metadata.json
index d080edd..5807bd4 100644
--- a/.repo-metadata.json
+++ b/.repo-metadata.json
@@ -2,8 +2,8 @@
   "name": "apigeeregistry",
   "name_pretty": "Apigee Registry API",
   "product_documentation": "https://cloud.google.com/apigee/docs/api-hub/get-started-registry-api",
-  "client_documentation": "https://cloud.google.com/nodejs/docs/reference/apigeeregistry/latest",
-  "issue_tracker": "https://github.com/googleapis/nodejs-video-transcoder/issues",
+  "client_documentation": "https://cloud.google.com/nodejs/docs/reference/apigee-registry/latest",
+  "issue_tracker": "https://github.com/googleapis/nodejs-apigee-registry/issues",
   "release_level": "beta",
   "language": "nodejs",
   "repo": "googleapis/nodejs-apigee-registry",
diff --git a/README.md b/README.md
index 8dd1af2..b41032a 100644
--- a/README.md
+++ b/README.md
@@ -117,7 +117,7 @@ Apache Version 2.0
 
 See [LICENSE](https://github.com/googleapis/nodejs-apigee-registry/blob/main/LICENSE)
 
-[client-docs]: https://cloud.google.com/nodejs/docs/reference/apigeeregistry/latest
+[client-docs]: https://cloud.google.com/nodejs/docs/reference/apigee-registry/latest
 [product-docs]: https://cloud.google.com/apigee/docs/api-hub/get-started-registry-api
 [shell_img]: https://gstatic.com/cloudssh/images/open-btn.png
 [projects]: https://console.cloud.google.com/project
diff --git a/src/v1/provisioning_client.ts b/src/v1/provisioning_client.ts
index 122b3c9..ecfe3d3 100644
--- a/src/v1/provisioning_client.ts
+++ b/src/v1/provisioning_client.ts
@@ -634,7 +634,7 @@ export class ProvisioningClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.getInstance(request, options, callback);
@@ -743,7 +743,7 @@ export class ProvisioningClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.createInstance(request, options, callback);
@@ -882,7 +882,7 @@ export class ProvisioningClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.deleteInstance(request, options, callback);
diff --git a/src/v1/registry_client.ts b/src/v1/registry_client.ts
index 3bcb8ba..11b1bd0 100644
--- a/src/v1/registry_client.ts
+++ b/src/v1/registry_client.ts
@@ -23,7 +23,6 @@ import type {
   CallOptions,
   Descriptors,
   ClientOptions,
-  GrpcClientOptions,
   PaginationCallback,
   GaxCall,
   IamClient,
@@ -67,7 +66,6 @@ export class RegistryClient {
   iamClient: IamClient;
   locationsClient: LocationsClient;
   pathTemplates: {[name: string]: gax.PathTemplate};
-  operationsClient: gax.OperationsClient;
   registryStub?: Promise<{[name: string]: Function}>;
 
   /**
@@ -271,167 +269,6 @@ export class RegistryClient {
       ),
     };
 
-    const protoFilesRoot = this._gaxModule.protobuf.Root.fromJSON(jsonProtos);
-    // This API contains "long-running operations", which return a
-    // an Operation object that allows for tracking of the operation,
-    // rather than holding a request open.
-    const lroOptions: GrpcClientOptions = {
-      auth: this.auth,
-      grpc: 'grpc' in this._gaxGrpc ? this._gaxGrpc.grpc : undefined,
-    };
-    if (opts.fallback === 'rest') {
-      lroOptions.protoJson = protoFilesRoot;
-      lroOptions.httpRules = [
-        {
-          selector: 'google.cloud.location.Locations.GetLocation',
-          get: '/v1/{name=projects/*/locations/*}',
-        },
-        {
-          selector: 'google.cloud.location.Locations.ListLocations',
-          get: '/v1/{name=projects/*}/locations',
-        },
-        {
-          selector: 'google.iam.v1.IAMPolicy.GetIamPolicy',
-          get: '/v1/{resource=projects/*/locations/*/apis/*}:getIamPolicy',
-          additional_bindings: [
-            {
-              get: '/v1/{resource=projects/*/locations/*/apis/*/deployments/*}:getIamPolicy',
-            },
-            {
-              get: '/v1/{resource=projects/*/locations/*/apis/*/versions/*}:getIamPolicy',
-            },
-            {
-              get: '/v1/{resource=projects/*/locations/*/apis/*/versions/*/specs/*}:getIamPolicy',
-            },
-            {
-              get: '/v1/{resource=projects/*/locations/*/artifacts/*}:getIamPolicy',
-            },
-            {
-              get: '/v1/{resource=projects/*/locations/*/apis/*/artifacts/*}:getIamPolicy',
-            },
-            {
-              get: '/v1/{resource=projects/*/locations/*/apis/*/versions/*/artifacts/*}:getIamPolicy',
-            },
-            {
-              get: '/v1/{resource=projects/*/locations/*/apis/*/versions/*/specs/*/artifacts/*}:getIamPolicy',
-            },
-            {
-              get: '/v1/{resource=projects/*/locations/*/instances/*}:getIamPolicy',
-            },
-            {get: '/v1/{resource=projects/*/locations/*/runtime}:getIamPolicy'},
-          ],
-        },
-        {
-          selector: 'google.iam.v1.IAMPolicy.SetIamPolicy',
-          post: '/v1/{resource=projects/*/locations/*/apis/*}:setIamPolicy',
-          body: '*',
-          additional_bindings: [
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/deployments/*}:setIamPolicy',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/versions/*}:setIamPolicy',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/versions/*/specs/*}:setIamPolicy',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/artifacts/*}:setIamPolicy',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/artifacts/*}:setIamPolicy',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/versions/*/artifacts/*}:setIamPolicy',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/versions/*/specs/*/artifacts/*}:setIamPolicy',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/instances/*}:setIamPolicy',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/runtime}:setIamPolicy',
-              body: '*',
-            },
-          ],
-        },
-        {
-          selector: 'google.iam.v1.IAMPolicy.TestIamPermissions',
-          post: '/v1/{resource=projects/*/locations/*/apis/*}:testIamPermissions',
-          body: '*',
-          additional_bindings: [
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/deployments/*}:testIamPermissions',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/versions/*}:testIamPermissions',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/versions/*/specs/*}:testIamPermissions',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/artifacts/*}:testIamPermissions',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/artifacts/*}:testIamPermissions',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/versions/*/artifacts/*}:testIamPermissions',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/apis/*/versions/*/specs/*/artifacts/*}:testIamPermissions',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/instances/*}:testIamPermissions',
-              body: '*',
-            },
-            {
-              post: '/v1/{resource=projects/*/locations/*/runtime}:testIamPermissions',
-              body: '*',
-            },
-          ],
-        },
-        {
-          selector: 'google.longrunning.Operations.CancelOperation',
-          post: '/v1/{name=projects/*/locations/*/operations/*}:cancel',
-          body: '*',
-        },
-        {
-          selector: 'google.longrunning.Operations.DeleteOperation',
-          delete: '/v1/{name=projects/*/locations/*/operations/*}',
-        },
-        {
-          selector: 'google.longrunning.Operations.GetOperation',
-          get: '/v1/{name=projects/*/locations/*/operations/*}',
-        },
-        {
-          selector: 'google.longrunning.Operations.ListOperations',
-          get: '/v1/{name=projects/*/locations/*}/operations',
-        },
-      ];
-    }
-    this.operationsClient = this._gaxModule
-      .lro(lroOptions)
-      .operationsClient(opts);
-
-    this.descriptors.longrunning = {};
-
     // Put together the default options sent with requests.
     this._defaults = this._gaxGrpc.constructSettings(
       'google.cloud.apigeeregistry.v1.Registry',
@@ -681,7 +518,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.getApi(request, options, callback);
@@ -783,7 +620,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.createApi(request, options, callback);
@@ -885,7 +722,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        'api.name': request.api!.name || '',
+        'api.name': request.api!.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.updateApi(request, options, callback);
@@ -981,7 +818,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.deleteApi(request, options, callback);
@@ -1073,7 +910,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.getApiVersion(request, options, callback);
@@ -1181,7 +1018,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.createApiVersion(request, options, callback);
@@ -1289,7 +1126,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        'api_version.name': request.apiVersion!.name || '',
+        'api_version.name': request.apiVersion!.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.updateApiVersion(request, options, callback);
@@ -1391,7 +1228,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.deleteApiVersion(request, options, callback);
@@ -1483,7 +1320,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.getApiSpec(request, options, callback);
@@ -1584,7 +1421,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.getApiSpecContents(request, options, callback);
@@ -1686,7 +1523,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.createApiSpec(request, options, callback);
@@ -1788,7 +1625,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        'api_spec.name': request.apiSpec!.name || '',
+        'api_spec.name': request.apiSpec!.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.updateApiSpec(request, options, callback);
@@ -1884,7 +1721,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.deleteApiSpec(request, options, callback);
@@ -1984,7 +1821,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.tagApiSpecRevision(request, options, callback);
@@ -2081,7 +1918,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.rollbackApiSpec(request, options, callback);
@@ -2182,7 +2019,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.deleteApiSpecRevision(request, options, callback);
@@ -2280,7 +2117,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.getApiDeployment(request, options, callback);
@@ -2388,7 +2225,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.createApiDeployment(request, options, callback);
@@ -2496,7 +2333,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        'api_deployment.name': request.apiDeployment!.name || '',
+        'api_deployment.name': request.apiDeployment!.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.updateApiDeployment(request, options, callback);
@@ -2598,7 +2435,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.deleteApiDeployment(request, options, callback);
@@ -2699,7 +2536,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.tagApiDeploymentRevision(
@@ -2806,7 +2643,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.rollbackApiDeployment(request, options, callback);
@@ -2907,7 +2744,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.deleteApiDeploymentRevision(
@@ -3003,7 +2840,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.getArtifact(request, options, callback);
@@ -3104,7 +2941,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.getArtifactContents(request, options, callback);
@@ -3206,7 +3043,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.createArtifact(request, options, callback);
@@ -3300,7 +3137,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        'artifact.name': request.artifact!.name || '',
+        'artifact.name': request.artifact!.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.replaceArtifact(request, options, callback);
@@ -3392,7 +3229,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.deleteArtifact(request, options, callback);
@@ -3502,7 +3339,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.listApis(request, options, callback);
@@ -3551,7 +3388,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listApis'];
     const callSettings = defaultCallSettings.merge(options);
@@ -3609,7 +3446,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listApis'];
     const callSettings = defaultCallSettings.merge(options);
@@ -3724,7 +3561,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.listApiVersions(request, options, callback);
@@ -3773,7 +3610,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listApiVersions'];
     const callSettings = defaultCallSettings.merge(options);
@@ -3831,7 +3668,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listApiVersions'];
     const callSettings = defaultCallSettings.merge(options);
@@ -3946,7 +3783,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.listApiSpecs(request, options, callback);
@@ -3995,7 +3832,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listApiSpecs'];
     const callSettings = defaultCallSettings.merge(options);
@@ -4053,7 +3890,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listApiSpecs'];
     const callSettings = defaultCallSettings.merge(options);
@@ -4159,7 +3996,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.listApiSpecRevisions(request, options, callback);
@@ -4198,7 +4035,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     const defaultCallSettings = this._defaults['listApiSpecRevisions'];
     const callSettings = defaultCallSettings.merge(options);
@@ -4246,7 +4083,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     const defaultCallSettings = this._defaults['listApiSpecRevisions'];
     const callSettings = defaultCallSettings.merge(options);
@@ -4361,7 +4198,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.listApiDeployments(request, options, callback);
@@ -4410,7 +4247,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listApiDeployments'];
     const callSettings = defaultCallSettings.merge(options);
@@ -4468,7 +4305,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listApiDeployments'];
     const callSettings = defaultCallSettings.merge(options);
@@ -4574,7 +4411,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     this.initialize();
     return this.innerApiCalls.listApiDeploymentRevisions(
@@ -4617,7 +4454,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     const defaultCallSettings = this._defaults['listApiDeploymentRevisions'];
     const callSettings = defaultCallSettings.merge(options);
@@ -4665,7 +4502,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        name: request.name || '',
+        name: request.name ?? '',
       });
     const defaultCallSettings = this._defaults['listApiDeploymentRevisions'];
     const callSettings = defaultCallSettings.merge(options);
@@ -4780,7 +4617,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     this.initialize();
     return this.innerApiCalls.listArtifacts(request, options, callback);
@@ -4829,7 +4666,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listArtifacts'];
     const callSettings = defaultCallSettings.merge(options);
@@ -4887,7 +4724,7 @@ export class RegistryClient {
     options.otherArgs.headers = options.otherArgs.headers || {};
     options.otherArgs.headers['x-goog-request-params'] =
       this._gaxModule.routingHeader.fromParams({
-        parent: request.parent || '',
+        parent: request.parent ?? '',
       });
     const defaultCallSettings = this._defaults['listArtifacts'];
     const callSettings = defaultCallSettings.merge(options);
@@ -5118,183 +4955,6 @@ export class RegistryClient {
     return this.locationsClient.listLocationsAsync(request, options);
   }
 
-  /**
-   * Gets the latest state of a long-running operation.  Clients can use this
-   * method to poll the operation result at intervals as recommended by the API
-   * service.
-   *
-   * @param {Object} request - The request object that will be sent.
-   * @param {string} request.name - The name of the operation resource.
-   * @param {Object=} options
-   *   Optional parameters. You can override the default settings for this call,
-   *   e.g, timeout, retries, paginations, etc. See [gax.CallOptions]{@link
-   *   https://googleapis.github.io/gax-nodejs/global.html#CallOptions} for the
-   *   details.
-   * @param {function(?Error, ?Object)=} callback
-   *   The function which will be called with the result of the API call.
-   *
-   *   The second parameter to the callback is an object representing
-   * [google.longrunning.Operation]{@link
-   * external:"google.longrunning.Operation"}.
-   * @return {Promise} - The promise which resolves to an array.
-   *   The first element of the array is an object representing
-   * [google.longrunning.Operation]{@link
-   * external:"google.longrunning.Operation"}. The promise has a method named
-   * "cancel" which cancels the ongoing API call.
-   *
-   * @example
-   * ```
-   * const client = longrunning.operationsClient();
-   * const name = '';
-   * const [response] = await client.getOperation({name});
-   * // doThingsWith(response)
-   * ```
-   */
-  getOperation(
-    request: protos.google.longrunning.GetOperationRequest,
-    options?:
-      | gax.CallOptions
-      | Callback<
-          protos.google.longrunning.Operation,
-          protos.google.longrunning.GetOperationRequest,
-          {} | null | undefined
-        >,
-    callback?: Callback<
-      protos.google.longrunning.Operation,
-      protos.google.longrunning.GetOperationRequest,
-      {} | null | undefined
-    >
-  ): Promise<[protos.google.longrunning.Operation]> {
-    return this.operationsClient.getOperation(request, options, callback);
-  }
-  /**
-   * Lists operations that match the specified filter in the request. If the
-   * server doesn't support this method, it returns `UNIMPLEMENTED`. Returns an iterable object.
-   *
-   * For-await-of syntax is used with the iterable to recursively get response element on-demand.
-   *
-   * @param {Object} request - The request object that will be sent.
-   * @param {string} request.name - The name of the operation collection.
-   * @param {string} request.filter - The standard list filter.
-   * @param {number=} request.pageSize -
-   *   The maximum number of resources contained in the underlying API
-   *   response. If page streaming is performed per-resource, this
-   *   parameter does not affect the return value. If page streaming is
-   *   performed per-page, this determines the maximum number of
-   *   resources in a page.
-   * @param {Object=} options
-   *   Optional parameters. You can override the default settings for this call,
-   *   e.g, timeout, retries, paginations, etc. See [gax.CallOptions]{@link
-   *   https://googleapis.github.io/gax-nodejs/global.html#CallOptions} for the
-   *   details.
-   * @returns {Object}
-   *   An iterable Object that conforms to @link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols.
-   *
-   * @example
-   * ```
-   * const client = longrunning.operationsClient();
-   * for await (const response of client.listOperationsAsync(request));
-   * // doThingsWith(response)
-   * ```
-   */
-  listOperationsAsync(
-    request: protos.google.longrunning.ListOperationsRequest,
-    options?: gax.CallOptions
-  ): AsyncIterable<protos.google.longrunning.ListOperationsResponse> {
-    return this.operationsClient.listOperationsAsync(request, options);
-  }
-  /**
-   * Starts asynchronous cancellation on a long-running operation.  The server
-   * makes a best effort to cancel the operation, but success is not
-   * guaranteed.  If the server doesn't support this method, it returns
-   * `google.rpc.Code.UNIMPLEMENTED`.  Clients can use
-   * {@link Operations.GetOperation} or
-   * other methods to check whether the cancellation succeeded or whether the
-   * operation completed despite cancellation. On successful cancellation,
-   * the operation is not deleted; instead, it becomes an operation with
-   * an {@link Operation.error} value with a {@link google.rpc.Status.code} of
-   * 1, corresponding to `Code.CANCELLED`.
-   *
-   * @param {Object} request - The request object that will be sent.
-   * @param {string} request.name - The name of the operation resource to be cancelled.
-   * @param {Object=} options
-   *   Optional parameters. You can override the default settings for this call,
-   * e.g, timeout, retries, paginations, etc. See [gax.CallOptions]{@link
-   * https://googleapis.github.io/gax-nodejs/global.html#CallOptions} for the
-   * details.
-   * @param {function(?Error)=} callback
-   *   The function which will be called with the result of the API call.
-   * @return {Promise} - The promise which resolves when API call finishes.
-   *   The promise has a method named "cancel" which cancels the ongoing API
-   * call.
-   *
-   * @example
-   * ```
-   * const client = longrunning.operationsClient();
-   * await client.cancelOperation({name: ''});
-   * ```
-   */
-  cancelOperation(
-    request: protos.google.longrunning.CancelOperationRequest,
-    options?:
-      | gax.CallOptions
-      | Callback<
-          protos.google.protobuf.Empty,
-          protos.google.longrunning.CancelOperationRequest,
-          {} | undefined | null
-        >,
-    callback?: Callback<
-      protos.google.longrunning.CancelOperationRequest,
-      protos.google.protobuf.Empty,
-      {} | undefined | null
-    >
-  ): Promise<protos.google.protobuf.Empty> {
-    return this.operationsClient.cancelOperation(request, options, callback);
-  }
-
-  /**
-   * Deletes a long-running operation. This method indicates that the client is
-   * no longer interested in the operation result. It does not cancel the
-   * operation. If the server doesn't support this method, it returns
-   * `google.rpc.Code.UNIMPLEMENTED`.
-   *
-   * @param {Object} request - The request object that will be sent.
-   * @param {string} request.name - The name of the operation resource to be deleted.
-   * @param {Object=} options
-   *   Optional parameters. You can override the default settings for this call,
-   * e.g, timeout, retries, paginations, etc. See [gax.CallOptions]{@link
-   * https://googleapis.github.io/gax-nodejs/global.html#CallOptions} for the
-   * details.
-   * @param {function(?Error)=} callback
-   *   The function which will be called with the result of the API call.
-   * @return {Promise} - The promise which resolves when API call finishes.
-   *   The promise has a method named "cancel" which cancels the ongoing API
-   * call.
-   *
-   * @example
-   * ```
-   * const client = longrunning.operationsClient();
-   * await client.deleteOperation({name: ''});
-   * ```
-   */
-  deleteOperation(
-    request: protos.google.longrunning.DeleteOperationRequest,
-    options?:
-      | gax.CallOptions
-      | Callback<
-          protos.google.protobuf.Empty,
-          protos.google.longrunning.DeleteOperationRequest,
-          {} | null | undefined
-        >,
-    callback?: Callback<
-      protos.google.protobuf.Empty,
-      protos.google.longrunning.DeleteOperationRequest,
-      {} | null | undefined
-    >
-  ): Promise<protos.google.protobuf.Empty> {
-    return this.operationsClient.deleteOperation(request, options, callback);
-  }
-
   // --------------------
   // -- Path templates --
   // --------------------
@@ -6166,7 +5826,6 @@ export class RegistryClient {
         stub.close();
         this.iamClient.close();
         this.locationsClient.close();
-        this.operationsClient.close();
       });
     }
     return Promise.resolve();
diff --git a/test/gapic_provisioning_v1.ts b/test/gapic_provisioning_v1.ts
index 2928629..a87c8a6 100644
--- a/test/gapic_provisioning_v1.ts
+++ b/test/gapic_provisioning_v1.ts
@@ -31,6 +31,21 @@ import {
   LocationProtos,
 } from 'google-gax';
 
+// Dynamically loaded proto JSON is needed to get the type information
+// to fill in default values for request objects
+const root = protobuf.Root.fromJSON(
+  require('../protos/protos.json')
+).resolveAll();
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+function getTypeDefaultValue(typeName: string, fields: string[]) {
+  let type = root.lookupType(typeName) as protobuf.Type;
+  for (const field of fields.slice(0, -1)) {
+    type = type.fields[field]?.resolvedType as protobuf.Type;
+  }
+  return type.fields[fields[fields.length - 1]]?.defaultValue;
+}
+
 function generateSampleMessage<T extends object>(instance: T) {
   const filledObject = (
     instance.constructor as typeof protobuf.Message
@@ -218,26 +233,26 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetInstanceRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetInstanceRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Instance()
       );
       client.innerApiCalls.getInstance = stubSimpleCall(expectedResponse);
       const [response] = await client.getInstance(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getInstance without error using callback', async () => {
@@ -249,15 +264,12 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetInstanceRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetInstanceRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Instance()
       );
@@ -280,11 +292,14 @@ describe('v1.ProvisioningClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getInstance with error', async () => {
@@ -296,26 +311,26 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetInstanceRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetInstanceRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.getInstance = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.getInstance(request), expectedError);
-      assert(
-        (client.innerApiCalls.getInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getInstance with closed client', async () => {
@@ -327,7 +342,11 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetInstanceRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetInstanceRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.getInstance(request), expectedError);
@@ -344,15 +363,12 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateInstanceRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateInstanceRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.longrunning.Operation()
       );
@@ -361,11 +377,14 @@ describe('v1.ProvisioningClient', () => {
       const [operation] = await client.createInstance(request);
       const [response] = await operation.promise();
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createInstance without error using callback', async () => {
@@ -377,15 +396,12 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateInstanceRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateInstanceRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.longrunning.Operation()
       );
@@ -415,11 +431,14 @@ describe('v1.ProvisioningClient', () => {
       >;
       const [response] = await operation.promise();
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createInstance with call error', async () => {
@@ -431,26 +450,26 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateInstanceRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateInstanceRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.createInstance = stubLongRunningCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.createInstance(request), expectedError);
-      assert(
-        (client.innerApiCalls.createInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createInstance with LRO error', async () => {
@@ -462,15 +481,12 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateInstanceRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateInstanceRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.createInstance = stubLongRunningCall(
         undefined,
@@ -479,11 +495,14 @@ describe('v1.ProvisioningClient', () => {
       );
       const [operation] = await client.createInstance(request);
       await assert.rejects(operation.promise(), expectedError);
-      assert(
-        (client.innerApiCalls.createInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes checkCreateInstanceProgress without error', async () => {
@@ -538,15 +557,12 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteInstanceRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteInstanceRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.longrunning.Operation()
       );
@@ -555,11 +571,14 @@ describe('v1.ProvisioningClient', () => {
       const [operation] = await client.deleteInstance(request);
       const [response] = await operation.promise();
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteInstance without error using callback', async () => {
@@ -571,15 +590,12 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteInstanceRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteInstanceRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.longrunning.Operation()
       );
@@ -609,11 +625,14 @@ describe('v1.ProvisioningClient', () => {
       >;
       const [response] = await operation.promise();
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteInstance with call error', async () => {
@@ -625,26 +644,26 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteInstanceRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteInstanceRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.deleteInstance = stubLongRunningCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.deleteInstance(request), expectedError);
-      assert(
-        (client.innerApiCalls.deleteInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteInstance with LRO error', async () => {
@@ -656,15 +675,12 @@ describe('v1.ProvisioningClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteInstanceRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteInstanceRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.deleteInstance = stubLongRunningCall(
         undefined,
@@ -673,11 +689,14 @@ describe('v1.ProvisioningClient', () => {
       );
       const [operation] = await client.deleteInstance(request);
       await assert.rejects(operation.promise(), expectedError);
-      assert(
-        (client.innerApiCalls.deleteInstance as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteInstance as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteInstance as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes checkDeleteInstanceProgress without error', async () => {
@@ -1192,12 +1211,15 @@ describe('v1.ProvisioningClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
+      assert(
         (
           client.locationsClient.descriptors.page.listLocations
             .asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+        )
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
     it('uses async iteration with listLocations with error', async () => {
@@ -1228,12 +1250,15 @@ describe('v1.ProvisioningClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
+      assert(
         (
           client.locationsClient.descriptors.page.listLocations
             .asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+        )
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
   });
diff --git a/test/gapic_registry_v1.ts b/test/gapic_registry_v1.ts
index 5b982c4..369b42c 100644
--- a/test/gapic_registry_v1.ts
+++ b/test/gapic_registry_v1.ts
@@ -25,12 +25,22 @@ import * as registryModule from '../src';
 
 import {PassThrough} from 'stream';
 
-import {
-  protobuf,
-  operationsProtos,
-  IamProtos,
-  LocationProtos,
-} from 'google-gax';
+import {protobuf, IamProtos, LocationProtos} from 'google-gax';
+
+// Dynamically loaded proto JSON is needed to get the type information
+// to fill in default values for request objects
+const root = protobuf.Root.fromJSON(
+  require('../protos/protos.json')
+).resolveAll();
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+function getTypeDefaultValue(typeName: string, fields: string[]) {
+  let type = root.lookupType(typeName) as protobuf.Type;
+  for (const field of fields.slice(0, -1)) {
+    type = type.fields[field]?.resolvedType as protobuf.Type;
+  }
+  return type.fields[fields[fields.length - 1]]?.defaultValue;
+}
 
 function generateSampleMessage<T extends object>(instance: T) {
   const filledObject = (
@@ -225,26 +235,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Api()
       );
       client.innerApiCalls.getApi = stubSimpleCall(expectedResponse);
       const [response] = await client.getApi(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (client.innerApiCalls.getApi as SinonStub).getCall(
+        0
+      ).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApi without error using callback', async () => {
@@ -256,15 +266,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Api()
       );
@@ -287,11 +294,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (client.innerApiCalls.getApi as SinonStub).getCall(
+        0
+      ).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApi with error', async () => {
@@ -303,23 +313,23 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.getApi = stubSimpleCall(undefined, expectedError);
       await assert.rejects(client.getApi(request), expectedError);
-      assert(
-        (client.innerApiCalls.getApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (client.innerApiCalls.getApi as SinonStub).getCall(
+        0
+      ).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApi with closed client', async () => {
@@ -331,7 +341,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.getApi(request), expectedError);
@@ -348,26 +362,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Api()
       );
       client.innerApiCalls.createApi = stubSimpleCall(expectedResponse);
       const [response] = await client.createApi(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApi as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApi without error using callback', async () => {
@@ -379,15 +393,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Api()
       );
@@ -410,11 +421,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApi as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApi with error', async () => {
@@ -426,23 +440,23 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.createApi = stubSimpleCall(undefined, expectedError);
       await assert.rejects(client.createApi(request), expectedError);
-      assert(
-        (client.innerApiCalls.createApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApi as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApi with closed client', async () => {
@@ -454,7 +468,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiRequest()
       );
-      request.parent = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.createApi(request), expectedError);
@@ -471,27 +489,27 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiRequest()
       );
-      request.api = {};
-      request.api.name = '';
-      const expectedHeaderRequestParams = 'api.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.api ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiRequest',
+        ['api', 'name']
+      );
+      request.api.name = defaultValue1;
+      const expectedHeaderRequestParams = `api.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Api()
       );
       client.innerApiCalls.updateApi = stubSimpleCall(expectedResponse);
       const [response] = await client.updateApi(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.updateApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApi as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApi without error using callback', async () => {
@@ -503,16 +521,13 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiRequest()
       );
-      request.api = {};
-      request.api.name = '';
-      const expectedHeaderRequestParams = 'api.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.api ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiRequest',
+        ['api', 'name']
+      );
+      request.api.name = defaultValue1;
+      const expectedHeaderRequestParams = `api.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Api()
       );
@@ -535,11 +550,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.updateApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApi as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApi with error', async () => {
@@ -551,24 +569,24 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiRequest()
       );
-      request.api = {};
-      request.api.name = '';
-      const expectedHeaderRequestParams = 'api.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.api ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiRequest',
+        ['api', 'name']
+      );
+      request.api.name = defaultValue1;
+      const expectedHeaderRequestParams = `api.name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.updateApi = stubSimpleCall(undefined, expectedError);
       await assert.rejects(client.updateApi(request), expectedError);
-      assert(
-        (client.innerApiCalls.updateApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApi as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApi with closed client', async () => {
@@ -580,8 +598,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiRequest()
       );
-      request.api = {};
-      request.api.name = '';
+      request.api ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiRequest',
+        ['api', 'name']
+      );
+      request.api.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.updateApi(request), expectedError);
@@ -598,26 +620,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
       client.innerApiCalls.deleteApi = stubSimpleCall(expectedResponse);
       const [response] = await client.deleteApi(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApi as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApi without error using callback', async () => {
@@ -629,15 +651,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
@@ -660,11 +679,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApi as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApi with error', async () => {
@@ -676,23 +698,23 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.deleteApi = stubSimpleCall(undefined, expectedError);
       await assert.rejects(client.deleteApi(request), expectedError);
-      assert(
-        (client.innerApiCalls.deleteApi as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApi as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApi as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApi with closed client', async () => {
@@ -704,7 +726,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.deleteApi(request), expectedError);
@@ -721,26 +747,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiVersionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiVersionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiVersion()
       );
       client.innerApiCalls.getApiVersion = stubSimpleCall(expectedResponse);
       const [response] = await client.getApiVersion(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiVersion without error using callback', async () => {
@@ -752,15 +778,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiVersionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiVersionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiVersion()
       );
@@ -783,11 +806,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiVersion with error', async () => {
@@ -799,26 +825,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiVersionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiVersionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.getApiVersion = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.getApiVersion(request), expectedError);
-      assert(
-        (client.innerApiCalls.getApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiVersion with closed client', async () => {
@@ -830,7 +856,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiVersionRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiVersionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.getApiVersion(request), expectedError);
@@ -847,26 +877,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiVersionRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiVersionRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiVersion()
       );
       client.innerApiCalls.createApiVersion = stubSimpleCall(expectedResponse);
       const [response] = await client.createApiVersion(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApiVersion without error using callback', async () => {
@@ -878,15 +908,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiVersionRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiVersionRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiVersion()
       );
@@ -909,11 +936,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApiVersion with error', async () => {
@@ -925,26 +955,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiVersionRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiVersionRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.createApiVersion = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.createApiVersion(request), expectedError);
-      assert(
-        (client.innerApiCalls.createApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApiVersion with closed client', async () => {
@@ -956,7 +986,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiVersionRequest()
       );
-      request.parent = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiVersionRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.createApiVersion(request), expectedError);
@@ -973,27 +1007,27 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiVersionRequest()
       );
-      request.apiVersion = {};
-      request.apiVersion.name = '';
-      const expectedHeaderRequestParams = 'api_version.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.apiVersion ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiVersionRequest',
+        ['apiVersion', 'name']
+      );
+      request.apiVersion.name = defaultValue1;
+      const expectedHeaderRequestParams = `api_version.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiVersion()
       );
       client.innerApiCalls.updateApiVersion = stubSimpleCall(expectedResponse);
       const [response] = await client.updateApiVersion(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.updateApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApiVersion without error using callback', async () => {
@@ -1005,16 +1039,13 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiVersionRequest()
       );
-      request.apiVersion = {};
-      request.apiVersion.name = '';
-      const expectedHeaderRequestParams = 'api_version.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.apiVersion ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiVersionRequest',
+        ['apiVersion', 'name']
+      );
+      request.apiVersion.name = defaultValue1;
+      const expectedHeaderRequestParams = `api_version.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiVersion()
       );
@@ -1037,11 +1068,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.updateApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApiVersion with error', async () => {
@@ -1053,27 +1087,27 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiVersionRequest()
       );
-      request.apiVersion = {};
-      request.apiVersion.name = '';
-      const expectedHeaderRequestParams = 'api_version.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.apiVersion ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiVersionRequest',
+        ['apiVersion', 'name']
+      );
+      request.apiVersion.name = defaultValue1;
+      const expectedHeaderRequestParams = `api_version.name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.updateApiVersion = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.updateApiVersion(request), expectedError);
-      assert(
-        (client.innerApiCalls.updateApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApiVersion with closed client', async () => {
@@ -1085,8 +1119,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiVersionRequest()
       );
-      request.apiVersion = {};
-      request.apiVersion.name = '';
+      request.apiVersion ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiVersionRequest',
+        ['apiVersion', 'name']
+      );
+      request.apiVersion.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.updateApiVersion(request), expectedError);
@@ -1103,26 +1141,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiVersionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiVersionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
       client.innerApiCalls.deleteApiVersion = stubSimpleCall(expectedResponse);
       const [response] = await client.deleteApiVersion(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiVersion without error using callback', async () => {
@@ -1134,15 +1172,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiVersionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiVersionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
@@ -1165,11 +1200,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiVersion with error', async () => {
@@ -1181,26 +1219,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiVersionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiVersionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.deleteApiVersion = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.deleteApiVersion(request), expectedError);
-      assert(
-        (client.innerApiCalls.deleteApiVersion as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiVersion as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiVersion as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiVersion with closed client', async () => {
@@ -1212,7 +1250,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiVersionRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiVersionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.deleteApiVersion(request), expectedError);
@@ -1229,26 +1271,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiSpecRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
       client.innerApiCalls.getApiSpec = stubSimpleCall(expectedResponse);
       const [response] = await client.getApiSpec(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiSpec without error using callback', async () => {
@@ -1260,15 +1302,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiSpecRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
@@ -1291,11 +1330,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiSpec with error', async () => {
@@ -1307,26 +1349,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiSpecRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.getApiSpec = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.getApiSpec(request), expectedError);
-      assert(
-        (client.innerApiCalls.getApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiSpec with closed client', async () => {
@@ -1338,7 +1380,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiSpecRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.getApiSpec(request), expectedError);
@@ -1355,15 +1401,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiSpecContentsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiSpecContentsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.api.HttpBody()
       );
@@ -1371,11 +1414,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.getApiSpecContents(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApiSpecContents as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiSpecContents as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiSpecContents as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiSpecContents without error using callback', async () => {
@@ -1387,15 +1433,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiSpecContentsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiSpecContentsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.api.HttpBody()
       );
@@ -1415,11 +1458,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApiSpecContents as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiSpecContents as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiSpecContents as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiSpecContents with error', async () => {
@@ -1431,26 +1477,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiSpecContentsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiSpecContentsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.getApiSpecContents = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.getApiSpecContents(request), expectedError);
-      assert(
-        (client.innerApiCalls.getApiSpecContents as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiSpecContents as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiSpecContents as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiSpecContents with closed client', async () => {
@@ -1462,7 +1508,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiSpecContentsRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiSpecContentsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.getApiSpecContents(request), expectedError);
@@ -1479,26 +1529,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiSpecRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiSpecRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
       client.innerApiCalls.createApiSpec = stubSimpleCall(expectedResponse);
       const [response] = await client.createApiSpec(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApiSpec without error using callback', async () => {
@@ -1510,15 +1560,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiSpecRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiSpecRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
@@ -1541,11 +1588,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApiSpec with error', async () => {
@@ -1557,26 +1607,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiSpecRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiSpecRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.createApiSpec = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.createApiSpec(request), expectedError);
-      assert(
-        (client.innerApiCalls.createApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApiSpec with closed client', async () => {
@@ -1588,7 +1638,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiSpecRequest()
       );
-      request.parent = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiSpecRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.createApiSpec(request), expectedError);
@@ -1605,27 +1659,27 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiSpecRequest()
       );
-      request.apiSpec = {};
-      request.apiSpec.name = '';
-      const expectedHeaderRequestParams = 'api_spec.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.apiSpec ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiSpecRequest',
+        ['apiSpec', 'name']
+      );
+      request.apiSpec.name = defaultValue1;
+      const expectedHeaderRequestParams = `api_spec.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
       client.innerApiCalls.updateApiSpec = stubSimpleCall(expectedResponse);
       const [response] = await client.updateApiSpec(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.updateApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApiSpec without error using callback', async () => {
@@ -1637,16 +1691,13 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiSpecRequest()
       );
-      request.apiSpec = {};
-      request.apiSpec.name = '';
-      const expectedHeaderRequestParams = 'api_spec.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.apiSpec ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiSpecRequest',
+        ['apiSpec', 'name']
+      );
+      request.apiSpec.name = defaultValue1;
+      const expectedHeaderRequestParams = `api_spec.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
@@ -1669,11 +1720,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.updateApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApiSpec with error', async () => {
@@ -1685,27 +1739,27 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiSpecRequest()
       );
-      request.apiSpec = {};
-      request.apiSpec.name = '';
-      const expectedHeaderRequestParams = 'api_spec.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.apiSpec ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiSpecRequest',
+        ['apiSpec', 'name']
+      );
+      request.apiSpec.name = defaultValue1;
+      const expectedHeaderRequestParams = `api_spec.name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.updateApiSpec = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.updateApiSpec(request), expectedError);
-      assert(
-        (client.innerApiCalls.updateApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApiSpec with closed client', async () => {
@@ -1717,8 +1771,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiSpecRequest()
       );
-      request.apiSpec = {};
-      request.apiSpec.name = '';
+      request.apiSpec ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiSpecRequest',
+        ['apiSpec', 'name']
+      );
+      request.apiSpec.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.updateApiSpec(request), expectedError);
@@ -1735,26 +1793,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiSpecRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
       client.innerApiCalls.deleteApiSpec = stubSimpleCall(expectedResponse);
       const [response] = await client.deleteApiSpec(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiSpec without error using callback', async () => {
@@ -1766,15 +1824,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiSpecRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
@@ -1797,11 +1852,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiSpec with error', async () => {
@@ -1813,26 +1871,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiSpecRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.deleteApiSpec = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.deleteApiSpec(request), expectedError);
-      assert(
-        (client.innerApiCalls.deleteApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiSpec with closed client', async () => {
@@ -1844,7 +1902,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiSpecRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.deleteApiSpec(request), expectedError);
@@ -1861,15 +1923,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.TagApiSpecRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.TagApiSpecRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
@@ -1877,11 +1936,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.tagApiSpecRevision(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.tagApiSpecRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.tagApiSpecRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.tagApiSpecRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes tagApiSpecRevision without error using callback', async () => {
@@ -1893,15 +1955,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.TagApiSpecRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.TagApiSpecRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
@@ -1924,11 +1983,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.tagApiSpecRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.tagApiSpecRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.tagApiSpecRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes tagApiSpecRevision with error', async () => {
@@ -1940,26 +2002,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.TagApiSpecRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.TagApiSpecRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.tagApiSpecRevision = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.tagApiSpecRevision(request), expectedError);
-      assert(
-        (client.innerApiCalls.tagApiSpecRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.tagApiSpecRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.tagApiSpecRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes tagApiSpecRevision with closed client', async () => {
@@ -1971,7 +2033,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.TagApiSpecRevisionRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.TagApiSpecRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.tagApiSpecRevision(request), expectedError);
@@ -1988,26 +2054,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.RollbackApiSpecRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.RollbackApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
       client.innerApiCalls.rollbackApiSpec = stubSimpleCall(expectedResponse);
       const [response] = await client.rollbackApiSpec(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.rollbackApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.rollbackApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.rollbackApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes rollbackApiSpec without error using callback', async () => {
@@ -2019,15 +2085,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.RollbackApiSpecRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.RollbackApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
@@ -2050,11 +2113,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.rollbackApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.rollbackApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.rollbackApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes rollbackApiSpec with error', async () => {
@@ -2066,26 +2132,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.RollbackApiSpecRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.RollbackApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.rollbackApiSpec = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.rollbackApiSpec(request), expectedError);
-      assert(
-        (client.innerApiCalls.rollbackApiSpec as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.rollbackApiSpec as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.rollbackApiSpec as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes rollbackApiSpec with closed client', async () => {
@@ -2097,7 +2163,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.RollbackApiSpecRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.RollbackApiSpecRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.rollbackApiSpec(request), expectedError);
@@ -2114,15 +2184,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiSpecRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiSpecRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
@@ -2130,11 +2197,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.deleteApiSpecRevision(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiSpecRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiSpecRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiSpecRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiSpecRevision without error using callback', async () => {
@@ -2146,15 +2216,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiSpecRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiSpecRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiSpec()
       );
@@ -2177,11 +2244,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiSpecRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiSpecRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiSpecRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiSpecRevision with error', async () => {
@@ -2193,15 +2263,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiSpecRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiSpecRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.deleteApiSpecRevision = stubSimpleCall(
         undefined,
@@ -2211,11 +2278,14 @@ describe('v1.RegistryClient', () => {
         client.deleteApiSpecRevision(request),
         expectedError
       );
-      assert(
-        (client.innerApiCalls.deleteApiSpecRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiSpecRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiSpecRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiSpecRevision with closed client', async () => {
@@ -2227,7 +2297,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiSpecRevisionRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiSpecRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(
@@ -2247,26 +2321,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiDeploymentRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
       client.innerApiCalls.getApiDeployment = stubSimpleCall(expectedResponse);
       const [response] = await client.getApiDeployment(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiDeployment without error using callback', async () => {
@@ -2278,15 +2352,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiDeploymentRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -2309,11 +2380,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiDeployment with error', async () => {
@@ -2325,26 +2399,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiDeploymentRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.getApiDeployment = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.getApiDeployment(request), expectedError);
-      assert(
-        (client.innerApiCalls.getApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getApiDeployment with closed client', async () => {
@@ -2356,7 +2430,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetApiDeploymentRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.getApiDeployment(request), expectedError);
@@ -2373,15 +2451,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiDeploymentRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiDeploymentRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -2389,11 +2464,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.createApiDeployment(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApiDeployment without error using callback', async () => {
@@ -2405,15 +2483,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiDeploymentRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiDeploymentRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -2436,11 +2511,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApiDeployment with error', async () => {
@@ -2452,26 +2530,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiDeploymentRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiDeploymentRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.createApiDeployment = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.createApiDeployment(request), expectedError);
-      assert(
-        (client.innerApiCalls.createApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createApiDeployment with closed client', async () => {
@@ -2483,7 +2561,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateApiDeploymentRequest()
       );
-      request.parent = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateApiDeploymentRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.createApiDeployment(request), expectedError);
@@ -2500,16 +2582,13 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiDeploymentRequest()
       );
-      request.apiDeployment = {};
-      request.apiDeployment.name = '';
-      const expectedHeaderRequestParams = 'api_deployment.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.apiDeployment ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiDeploymentRequest',
+        ['apiDeployment', 'name']
+      );
+      request.apiDeployment.name = defaultValue1;
+      const expectedHeaderRequestParams = `api_deployment.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -2517,11 +2596,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.updateApiDeployment(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.updateApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApiDeployment without error using callback', async () => {
@@ -2533,16 +2615,13 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiDeploymentRequest()
       );
-      request.apiDeployment = {};
-      request.apiDeployment.name = '';
-      const expectedHeaderRequestParams = 'api_deployment.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.apiDeployment ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiDeploymentRequest',
+        ['apiDeployment', 'name']
+      );
+      request.apiDeployment.name = defaultValue1;
+      const expectedHeaderRequestParams = `api_deployment.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -2565,11 +2644,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.updateApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApiDeployment with error', async () => {
@@ -2581,27 +2663,27 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiDeploymentRequest()
       );
-      request.apiDeployment = {};
-      request.apiDeployment.name = '';
-      const expectedHeaderRequestParams = 'api_deployment.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.apiDeployment ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiDeploymentRequest',
+        ['apiDeployment', 'name']
+      );
+      request.apiDeployment.name = defaultValue1;
+      const expectedHeaderRequestParams = `api_deployment.name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.updateApiDeployment = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.updateApiDeployment(request), expectedError);
-      assert(
-        (client.innerApiCalls.updateApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.updateApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.updateApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes updateApiDeployment with closed client', async () => {
@@ -2613,8 +2695,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.UpdateApiDeploymentRequest()
       );
-      request.apiDeployment = {};
-      request.apiDeployment.name = '';
+      request.apiDeployment ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.UpdateApiDeploymentRequest',
+        ['apiDeployment', 'name']
+      );
+      request.apiDeployment.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.updateApiDeployment(request), expectedError);
@@ -2631,15 +2717,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
@@ -2647,11 +2730,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.deleteApiDeployment(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiDeployment without error using callback', async () => {
@@ -2663,15 +2749,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
@@ -2694,11 +2777,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiDeployment with error', async () => {
@@ -2710,26 +2796,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.deleteApiDeployment = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.deleteApiDeployment(request), expectedError);
-      assert(
-        (client.innerApiCalls.deleteApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiDeployment with closed client', async () => {
@@ -2741,7 +2827,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.deleteApiDeployment(request), expectedError);
@@ -2758,15 +2848,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.TagApiDeploymentRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.TagApiDeploymentRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -2774,11 +2861,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.tagApiDeploymentRevision(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.tagApiDeploymentRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.tagApiDeploymentRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.tagApiDeploymentRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes tagApiDeploymentRevision without error using callback', async () => {
@@ -2790,15 +2880,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.TagApiDeploymentRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.TagApiDeploymentRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -2821,11 +2908,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.tagApiDeploymentRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.tagApiDeploymentRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.tagApiDeploymentRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes tagApiDeploymentRevision with error', async () => {
@@ -2837,15 +2927,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.TagApiDeploymentRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.TagApiDeploymentRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.tagApiDeploymentRevision = stubSimpleCall(
         undefined,
@@ -2855,11 +2942,14 @@ describe('v1.RegistryClient', () => {
         client.tagApiDeploymentRevision(request),
         expectedError
       );
-      assert(
-        (client.innerApiCalls.tagApiDeploymentRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.tagApiDeploymentRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.tagApiDeploymentRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes tagApiDeploymentRevision with closed client', async () => {
@@ -2871,7 +2961,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.TagApiDeploymentRevisionRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.TagApiDeploymentRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(
@@ -2891,15 +2985,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.RollbackApiDeploymentRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.RollbackApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -2907,11 +2998,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.rollbackApiDeployment(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.rollbackApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.rollbackApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.rollbackApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes rollbackApiDeployment without error using callback', async () => {
@@ -2923,15 +3017,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.RollbackApiDeploymentRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.RollbackApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -2954,11 +3045,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.rollbackApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.rollbackApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.rollbackApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes rollbackApiDeployment with error', async () => {
@@ -2970,15 +3064,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.RollbackApiDeploymentRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.RollbackApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.rollbackApiDeployment = stubSimpleCall(
         undefined,
@@ -2988,11 +3079,14 @@ describe('v1.RegistryClient', () => {
         client.rollbackApiDeployment(request),
         expectedError
       );
-      assert(
-        (client.innerApiCalls.rollbackApiDeployment as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.rollbackApiDeployment as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.rollbackApiDeployment as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes rollbackApiDeployment with closed client', async () => {
@@ -3004,7 +3098,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.RollbackApiDeploymentRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.RollbackApiDeploymentRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(
@@ -3024,15 +3122,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -3040,11 +3135,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.deleteApiDeploymentRevision(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiDeploymentRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiDeploymentRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiDeploymentRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiDeploymentRevision without error using callback', async () => {
@@ -3056,15 +3154,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
       );
@@ -3087,11 +3182,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteApiDeploymentRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiDeploymentRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiDeploymentRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiDeploymentRevision with error', async () => {
@@ -3103,15 +3201,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRevisionRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.deleteApiDeploymentRevision = stubSimpleCall(
         undefined,
@@ -3121,11 +3216,14 @@ describe('v1.RegistryClient', () => {
         client.deleteApiDeploymentRevision(request),
         expectedError
       );
-      assert(
-        (client.innerApiCalls.deleteApiDeploymentRevision as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteApiDeploymentRevision as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteApiDeploymentRevision as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteApiDeploymentRevision with closed client', async () => {
@@ -3137,7 +3235,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRevisionRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteApiDeploymentRevisionRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(
@@ -3157,26 +3259,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetArtifactRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetArtifactRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Artifact()
       );
       client.innerApiCalls.getArtifact = stubSimpleCall(expectedResponse);
       const [response] = await client.getArtifact(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getArtifact without error using callback', async () => {
@@ -3188,15 +3290,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetArtifactRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetArtifactRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Artifact()
       );
@@ -3219,11 +3318,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getArtifact with error', async () => {
@@ -3235,26 +3337,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetArtifactRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetArtifactRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.getArtifact = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.getArtifact(request), expectedError);
-      assert(
-        (client.innerApiCalls.getArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getArtifact with closed client', async () => {
@@ -3266,7 +3368,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetArtifactRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetArtifactRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.getArtifact(request), expectedError);
@@ -3283,15 +3389,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetArtifactContentsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetArtifactContentsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.api.HttpBody()
       );
@@ -3299,11 +3402,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.getArtifactContents(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getArtifactContents as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getArtifactContents as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getArtifactContents as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getArtifactContents without error using callback', async () => {
@@ -3315,15 +3421,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetArtifactContentsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetArtifactContentsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.api.HttpBody()
       );
@@ -3343,11 +3446,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.getArtifactContents as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getArtifactContents as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getArtifactContents as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getArtifactContents with error', async () => {
@@ -3359,26 +3465,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetArtifactContentsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetArtifactContentsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.getArtifactContents = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.getArtifactContents(request), expectedError);
-      assert(
-        (client.innerApiCalls.getArtifactContents as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.getArtifactContents as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.getArtifactContents as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes getArtifactContents with closed client', async () => {
@@ -3390,7 +3496,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.GetArtifactContentsRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.GetArtifactContentsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.getArtifactContents(request), expectedError);
@@ -3407,46 +3517,43 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateArtifactRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateArtifactRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Artifact()
       );
       client.innerApiCalls.createArtifact = stubSimpleCall(expectedResponse);
       const [response] = await client.createArtifact(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createArtifact without error using callback', async () => {
       const client = new registryModule.v1.RegistryClient({
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
-      });
-      client.initialize();
-      const request = generateSampleMessage(
-        new protos.google.cloud.apigeeregistry.v1.CreateArtifactRequest()
-      );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      });
+      client.initialize();
+      const request = generateSampleMessage(
+        new protos.google.cloud.apigeeregistry.v1.CreateArtifactRequest()
+      );
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateArtifactRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Artifact()
       );
@@ -3469,11 +3576,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.createArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createArtifact with error', async () => {
@@ -3485,26 +3595,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateArtifactRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateArtifactRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.createArtifact = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.createArtifact(request), expectedError);
-      assert(
-        (client.innerApiCalls.createArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.createArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.createArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes createArtifact with closed client', async () => {
@@ -3516,7 +3626,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.CreateArtifactRequest()
       );
-      request.parent = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.CreateArtifactRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.createArtifact(request), expectedError);
@@ -3533,27 +3647,27 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ReplaceArtifactRequest()
       );
-      request.artifact = {};
-      request.artifact.name = '';
-      const expectedHeaderRequestParams = 'artifact.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.artifact ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ReplaceArtifactRequest',
+        ['artifact', 'name']
+      );
+      request.artifact.name = defaultValue1;
+      const expectedHeaderRequestParams = `artifact.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Artifact()
       );
       client.innerApiCalls.replaceArtifact = stubSimpleCall(expectedResponse);
       const [response] = await client.replaceArtifact(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.replaceArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.replaceArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.replaceArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes replaceArtifact without error using callback', async () => {
@@ -3565,16 +3679,13 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ReplaceArtifactRequest()
       );
-      request.artifact = {};
-      request.artifact.name = '';
-      const expectedHeaderRequestParams = 'artifact.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.artifact ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ReplaceArtifactRequest',
+        ['artifact', 'name']
+      );
+      request.artifact.name = defaultValue1;
+      const expectedHeaderRequestParams = `artifact.name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.Artifact()
       );
@@ -3597,11 +3708,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.replaceArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.replaceArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.replaceArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes replaceArtifact with error', async () => {
@@ -3613,27 +3727,27 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ReplaceArtifactRequest()
       );
-      request.artifact = {};
-      request.artifact.name = '';
-      const expectedHeaderRequestParams = 'artifact.name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      request.artifact ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ReplaceArtifactRequest',
+        ['artifact', 'name']
+      );
+      request.artifact.name = defaultValue1;
+      const expectedHeaderRequestParams = `artifact.name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.replaceArtifact = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.replaceArtifact(request), expectedError);
-      assert(
-        (client.innerApiCalls.replaceArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.replaceArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.replaceArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes replaceArtifact with closed client', async () => {
@@ -3645,8 +3759,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ReplaceArtifactRequest()
       );
-      request.artifact = {};
-      request.artifact.name = '';
+      request.artifact ??= {};
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ReplaceArtifactRequest',
+        ['artifact', 'name']
+      );
+      request.artifact.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.replaceArtifact(request), expectedError);
@@ -3663,26 +3781,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteArtifactRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteArtifactRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
       client.innerApiCalls.deleteArtifact = stubSimpleCall(expectedResponse);
       const [response] = await client.deleteArtifact(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteArtifact without error using callback', async () => {
@@ -3694,15 +3812,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteArtifactRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteArtifactRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = generateSampleMessage(
         new protos.google.protobuf.Empty()
       );
@@ -3725,11 +3840,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.deleteArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteArtifact with error', async () => {
@@ -3741,26 +3859,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteArtifactRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteArtifactRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.deleteArtifact = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.deleteArtifact(request), expectedError);
-      assert(
-        (client.innerApiCalls.deleteArtifact as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.deleteArtifact as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.deleteArtifact as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes deleteArtifact with closed client', async () => {
@@ -3772,7 +3890,11 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.DeleteArtifactRequest()
       );
-      request.name = '';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.DeleteArtifactRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
       const expectedError = new Error('The client has already been closed.');
       client.close();
       await assert.rejects(client.deleteArtifact(request), expectedError);
@@ -3789,15 +3911,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApisRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApisRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(new protos.google.cloud.apigeeregistry.v1.Api()),
         generateSampleMessage(new protos.google.cloud.apigeeregistry.v1.Api()),
@@ -3806,11 +3925,14 @@ describe('v1.RegistryClient', () => {
       client.innerApiCalls.listApis = stubSimpleCall(expectedResponse);
       const [response] = await client.listApis(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApis as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApis as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApis as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApis without error using callback', async () => {
@@ -3822,15 +3944,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApisRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApisRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(new protos.google.cloud.apigeeregistry.v1.Api()),
         generateSampleMessage(new protos.google.cloud.apigeeregistry.v1.Api()),
@@ -3855,11 +3974,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApis as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApis as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApis as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApis with error', async () => {
@@ -3871,23 +3993,23 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApisRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApisRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.listApis = stubSimpleCall(undefined, expectedError);
       await assert.rejects(client.listApis(request), expectedError);
-      assert(
-        (client.innerApiCalls.listApis as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApis as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApis as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApisStream without error', async () => {
@@ -3899,8 +4021,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApisRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApisRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(new protos.google.cloud.apigeeregistry.v1.Api()),
         generateSampleMessage(new protos.google.cloud.apigeeregistry.v1.Api()),
@@ -3931,10 +4057,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApis, request)
       );
-      assert.strictEqual(
-        (client.descriptors.page.listApis.createStream as SinonStub).getCall(0)
-          .args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApis.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -3947,8 +4075,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApisRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApisRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApis.createStream = stubPageStreamingCall(
         undefined,
@@ -3976,10 +4108,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApis, request)
       );
-      assert.strictEqual(
-        (client.descriptors.page.listApis.createStream as SinonStub).getCall(0)
-          .args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApis.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -3992,8 +4126,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApisRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApisRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(new protos.google.cloud.apigeeregistry.v1.Api()),
         generateSampleMessage(new protos.google.cloud.apigeeregistry.v1.Api()),
@@ -4012,10 +4150,12 @@ describe('v1.RegistryClient', () => {
           .args[1],
         request
       );
-      assert.strictEqual(
-        (client.descriptors.page.listApis.asyncIterate as SinonStub).getCall(0)
-          .args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApis.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4028,8 +4168,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApisRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApisRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApis.asyncIterate = stubAsyncIterationCall(
         undefined,
@@ -4047,10 +4191,12 @@ describe('v1.RegistryClient', () => {
           .args[1],
         request
       );
-      assert.strictEqual(
-        (client.descriptors.page.listApis.asyncIterate as SinonStub).getCall(0)
-          .args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApis.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
   });
@@ -4065,15 +4211,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiVersionsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiVersionsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiVersion()
@@ -4088,11 +4231,14 @@ describe('v1.RegistryClient', () => {
       client.innerApiCalls.listApiVersions = stubSimpleCall(expectedResponse);
       const [response] = await client.listApiVersions(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiVersions as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiVersions as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiVersions as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiVersions without error using callback', async () => {
@@ -4104,15 +4250,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiVersionsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiVersionsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiVersion()
@@ -4143,11 +4286,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiVersions as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiVersions as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiVersions as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiVersions with error', async () => {
@@ -4159,26 +4305,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiVersionsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiVersionsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.listApiVersions = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.listApiVersions(request), expectedError);
-      assert(
-        (client.innerApiCalls.listApiVersions as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiVersions as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiVersions as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiVersionsStream without error', async () => {
@@ -4190,8 +4336,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiVersionsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiVersionsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiVersion()
@@ -4229,11 +4379,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiVersions, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiVersions.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiVersions.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4246,8 +4397,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiVersionsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiVersionsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiVersions.createStream =
         stubPageStreamingCall(undefined, expectedError);
@@ -4274,11 +4429,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiVersions, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiVersions.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiVersions.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4291,8 +4447,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiVersionsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiVersionsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiVersion()
@@ -4318,11 +4478,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiVersions.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiVersions.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4335,8 +4496,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiVersionsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiVersionsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiVersions.asyncIterate =
         stubAsyncIterationCall(undefined, expectedError);
@@ -4354,11 +4519,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiVersions.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiVersions.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
   });
@@ -4373,15 +4539,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiSpec()
@@ -4396,11 +4559,14 @@ describe('v1.RegistryClient', () => {
       client.innerApiCalls.listApiSpecs = stubSimpleCall(expectedResponse);
       const [response] = await client.listApiSpecs(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiSpecs as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiSpecs as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiSpecs as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiSpecs without error using callback', async () => {
@@ -4412,15 +4578,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiSpec()
@@ -4451,11 +4614,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiSpecs as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiSpecs as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiSpecs as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiSpecs with error', async () => {
@@ -4467,26 +4633,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.listApiSpecs = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.listApiSpecs(request), expectedError);
-      assert(
-        (client.innerApiCalls.listApiSpecs as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiSpecs as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiSpecs as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiSpecsStream without error', async () => {
@@ -4498,8 +4664,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiSpec()
@@ -4536,11 +4706,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiSpecs, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiSpecs.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiSpecs.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4553,8 +4724,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiSpecs.createStream = stubPageStreamingCall(
         undefined,
@@ -4582,11 +4757,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiSpecs, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiSpecs.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiSpecs.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4599,8 +4775,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiSpec()
@@ -4626,11 +4806,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiSpecs.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiSpecs.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4643,8 +4824,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiSpecs.asyncIterate =
         stubAsyncIterationCall(undefined, expectedError);
@@ -4661,11 +4846,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiSpecs.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiSpecs.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
   });
@@ -4680,15 +4866,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiSpec()
@@ -4704,11 +4887,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.listApiSpecRevisions(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiSpecRevisions as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiSpecRevisions as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiSpecRevisions as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiSpecRevisions without error using callback', async () => {
@@ -4720,15 +4906,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiSpec()
@@ -4759,11 +4942,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiSpecRevisions as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiSpecRevisions as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiSpecRevisions as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiSpecRevisions with error', async () => {
@@ -4775,26 +4961,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.listApiSpecRevisions = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.listApiSpecRevisions(request), expectedError);
-      assert(
-        (client.innerApiCalls.listApiSpecRevisions as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiSpecRevisions as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiSpecRevisions as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiSpecRevisionsStream without error', async () => {
@@ -4806,8 +4992,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiSpec()
@@ -4844,11 +5034,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiSpecRevisions, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiSpecRevisions.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiSpecRevisions.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4861,8 +5052,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiSpecRevisions.createStream =
         stubPageStreamingCall(undefined, expectedError);
@@ -4888,11 +5083,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiSpecRevisions, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiSpecRevisions.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiSpecRevisions.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4905,8 +5101,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiSpec()
@@ -4932,11 +5132,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiSpecRevisions.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiSpecRevisions.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -4949,8 +5150,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiSpecRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiSpecRevisions.asyncIterate =
         stubAsyncIterationCall(undefined, expectedError);
@@ -4967,11 +5172,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiSpecRevisions.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiSpecRevisions.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
   });
@@ -4986,15 +5192,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
@@ -5010,11 +5213,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.listApiDeployments(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiDeployments as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiDeployments as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiDeployments as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiDeployments without error using callback', async () => {
@@ -5026,15 +5232,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
@@ -5067,11 +5270,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiDeployments as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiDeployments as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiDeployments as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiDeployments with error', async () => {
@@ -5083,26 +5289,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.listApiDeployments = stubSimpleCall(
         undefined,
         expectedError
       );
       await assert.rejects(client.listApiDeployments(request), expectedError);
-      assert(
-        (client.innerApiCalls.listApiDeployments as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiDeployments as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiDeployments as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiDeploymentsStream without error', async () => {
@@ -5114,8 +5320,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
@@ -5153,11 +5363,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiDeployments, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiDeployments.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiDeployments.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -5170,8 +5381,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiDeployments.createStream =
         stubPageStreamingCall(undefined, expectedError);
@@ -5198,11 +5413,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiDeployments, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiDeployments.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiDeployments.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -5215,8 +5431,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
@@ -5243,11 +5463,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiDeployments.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiDeployments.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -5260,8 +5481,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiDeployments.asyncIterate =
         stubAsyncIterationCall(undefined, expectedError);
@@ -5279,11 +5504,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listApiDeployments.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listApiDeployments.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
   });
@@ -5298,15 +5524,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
@@ -5322,11 +5545,14 @@ describe('v1.RegistryClient', () => {
         stubSimpleCall(expectedResponse);
       const [response] = await client.listApiDeploymentRevisions(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiDeploymentRevisions as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiDeploymentRevisions as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiDeploymentRevisions as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiDeploymentRevisions without error using callback', async () => {
@@ -5338,15 +5564,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
@@ -5379,11 +5602,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listApiDeploymentRevisions as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiDeploymentRevisions as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiDeploymentRevisions as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiDeploymentRevisions with error', async () => {
@@ -5395,15 +5621,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.listApiDeploymentRevisions = stubSimpleCall(
         undefined,
@@ -5413,11 +5636,14 @@ describe('v1.RegistryClient', () => {
         client.listApiDeploymentRevisions(request),
         expectedError
       );
-      assert(
-        (client.innerApiCalls.listApiDeploymentRevisions as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listApiDeploymentRevisions as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listApiDeploymentRevisions as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listApiDeploymentRevisionsStream without error', async () => {
@@ -5429,8 +5655,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
@@ -5471,12 +5701,15 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiDeploymentRevisions, request)
       );
-      assert.strictEqual(
+      assert(
         (
           client.descriptors.page.listApiDeploymentRevisions
             .createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+        )
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -5489,8 +5722,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiDeploymentRevisions.createStream =
         stubPageStreamingCall(undefined, expectedError);
@@ -5520,12 +5757,15 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listApiDeploymentRevisions, request)
       );
-      assert.strictEqual(
+      assert(
         (
           client.descriptors.page.listApiDeploymentRevisions
             .createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+        )
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -5538,8 +5778,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.ApiDeployment()
@@ -5567,12 +5811,15 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
+      assert(
         (
           client.descriptors.page.listApiDeploymentRevisions
             .asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+        )
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -5585,8 +5832,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest()
       );
-      request.name = '';
-      const expectedHeaderRequestParams = 'name=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListApiDeploymentRevisionsRequest',
+        ['name']
+      );
+      request.name = defaultValue1;
+      const expectedHeaderRequestParams = `name=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listApiDeploymentRevisions.asyncIterate =
         stubAsyncIterationCall(undefined, expectedError);
@@ -5605,12 +5856,15 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
+      assert(
         (
           client.descriptors.page.listApiDeploymentRevisions
             .asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+        )
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
   });
@@ -5625,15 +5879,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListArtifactsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListArtifactsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.Artifact()
@@ -5648,11 +5899,14 @@ describe('v1.RegistryClient', () => {
       client.innerApiCalls.listArtifacts = stubSimpleCall(expectedResponse);
       const [response] = await client.listArtifacts(request);
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listArtifacts as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listArtifacts as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listArtifacts as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listArtifacts without error using callback', async () => {
@@ -5664,15 +5918,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListArtifactsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListArtifactsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.Artifact()
@@ -5703,11 +5954,14 @@ describe('v1.RegistryClient', () => {
       });
       const response = await promise;
       assert.deepStrictEqual(response, expectedResponse);
-      assert(
-        (client.innerApiCalls.listArtifacts as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions /*, callback defined above */)
-      );
+      const actualRequest = (
+        client.innerApiCalls.listArtifacts as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listArtifacts as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listArtifacts with error', async () => {
@@ -5719,26 +5973,26 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListArtifactsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
-      const expectedOptions = {
-        otherArgs: {
-          headers: {
-            'x-goog-request-params': expectedHeaderRequestParams,
-          },
-        },
-      };
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListArtifactsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.innerApiCalls.listArtifacts = stubSimpleCall(
         undefined,
-        expectedError
-      );
-      await assert.rejects(client.listArtifacts(request), expectedError);
-      assert(
-        (client.innerApiCalls.listArtifacts as SinonStub)
-          .getCall(0)
-          .calledWith(request, expectedOptions, undefined)
+        expectedError
       );
+      await assert.rejects(client.listArtifacts(request), expectedError);
+      const actualRequest = (
+        client.innerApiCalls.listArtifacts as SinonStub
+      ).getCall(0).args[0];
+      assert.deepStrictEqual(actualRequest, request);
+      const actualHeaderRequestParams = (
+        client.innerApiCalls.listArtifacts as SinonStub
+      ).getCall(0).args[1].otherArgs.headers['x-goog-request-params'];
+      assert(actualHeaderRequestParams.includes(expectedHeaderRequestParams));
     });
 
     it('invokes listArtifactsStream without error', async () => {
@@ -5750,8 +6004,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListArtifactsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListArtifactsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.Artifact()
@@ -5788,11 +6046,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listArtifacts, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listArtifacts.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listArtifacts.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -5805,8 +6064,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListArtifactsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListArtifactsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listArtifacts.createStream =
         stubPageStreamingCall(undefined, expectedError);
@@ -5832,11 +6095,12 @@ describe('v1.RegistryClient', () => {
           .getCall(0)
           .calledWith(client.innerApiCalls.listArtifacts, request)
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listArtifacts.createStream as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listArtifacts.createStream as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -5849,8 +6113,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListArtifactsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListArtifactsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedResponse = [
         generateSampleMessage(
           new protos.google.cloud.apigeeregistry.v1.Artifact()
@@ -5876,11 +6144,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listArtifacts.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listArtifacts.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
 
@@ -5893,8 +6162,12 @@ describe('v1.RegistryClient', () => {
       const request = generateSampleMessage(
         new protos.google.cloud.apigeeregistry.v1.ListArtifactsRequest()
       );
-      request.parent = '';
-      const expectedHeaderRequestParams = 'parent=';
+      const defaultValue1 = getTypeDefaultValue(
+        '.google.cloud.apigeeregistry.v1.ListArtifactsRequest',
+        ['parent']
+      );
+      request.parent = defaultValue1;
+      const expectedHeaderRequestParams = `parent=${defaultValue1}`;
       const expectedError = new Error('expected');
       client.descriptors.page.listArtifacts.asyncIterate =
         stubAsyncIterationCall(undefined, expectedError);
@@ -5911,11 +6184,12 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
-        (
-          client.descriptors.page.listArtifacts.asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+      assert(
+        (client.descriptors.page.listArtifacts.asyncIterate as SinonStub)
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
   });
@@ -6390,12 +6664,15 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
+      assert(
         (
           client.locationsClient.descriptors.page.listLocations
             .asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
+        )
+          .getCall(0)
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
     it('uses async iteration with listLocations with error', async () => {
@@ -6426,317 +6703,15 @@ describe('v1.RegistryClient', () => {
         ).getCall(0).args[1],
         request
       );
-      assert.strictEqual(
+      assert(
         (
           client.locationsClient.descriptors.page.listLocations
             .asyncIterate as SinonStub
-        ).getCall(0).args[2].otherArgs.headers['x-goog-request-params'],
-        expectedHeaderRequestParams
-      );
-    });
-  });
-  describe('getOperation', () => {
-    it('invokes getOperation without error', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      client.initialize();
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.GetOperationRequest()
-      );
-      const expectedResponse = generateSampleMessage(
-        new operationsProtos.google.longrunning.Operation()
-      );
-      client.operationsClient.getOperation = stubSimpleCall(expectedResponse);
-      const response = await client.getOperation(request);
-      assert.deepStrictEqual(response, [expectedResponse]);
-      assert(
-        (client.operationsClient.getOperation as SinonStub)
-          .getCall(0)
-          .calledWith(request)
-      );
-    });
-    it('invokes getOperation without error using callback', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.GetOperationRequest()
-      );
-      const expectedResponse = generateSampleMessage(
-        new operationsProtos.google.longrunning.Operation()
-      );
-      client.operationsClient.getOperation = sinon
-        .stub()
-        .callsArgWith(2, null, expectedResponse);
-      const promise = new Promise((resolve, reject) => {
-        client.operationsClient.getOperation(
-          request,
-          undefined,
-          (
-            err?: Error | null,
-            result?: operationsProtos.google.longrunning.Operation | null
-          ) => {
-            if (err) {
-              reject(err);
-            } else {
-              resolve(result);
-            }
-          }
-        );
-      });
-      const response = await promise;
-      assert.deepStrictEqual(response, expectedResponse);
-      assert((client.operationsClient.getOperation as SinonStub).getCall(0));
-    });
-    it('invokes getOperation with error', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.GetOperationRequest()
-      );
-      const expectedError = new Error('expected');
-      client.operationsClient.getOperation = stubSimpleCall(
-        undefined,
-        expectedError
-      );
-      await assert.rejects(async () => {
-        await client.getOperation(request);
-      }, expectedError);
-      assert(
-        (client.operationsClient.getOperation as SinonStub)
-          .getCall(0)
-          .calledWith(request)
-      );
-    });
-  });
-  describe('cancelOperation', () => {
-    it('invokes cancelOperation without error', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      client.initialize();
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.CancelOperationRequest()
-      );
-      const expectedResponse = generateSampleMessage(
-        new protos.google.protobuf.Empty()
-      );
-      client.operationsClient.cancelOperation =
-        stubSimpleCall(expectedResponse);
-      const response = await client.cancelOperation(request);
-      assert.deepStrictEqual(response, [expectedResponse]);
-      assert(
-        (client.operationsClient.cancelOperation as SinonStub)
-          .getCall(0)
-          .calledWith(request)
-      );
-    });
-    it('invokes cancelOperation without error using callback', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.CancelOperationRequest()
-      );
-      const expectedResponse = generateSampleMessage(
-        new protos.google.protobuf.Empty()
-      );
-      client.operationsClient.cancelOperation = sinon
-        .stub()
-        .callsArgWith(2, null, expectedResponse);
-      const promise = new Promise((resolve, reject) => {
-        client.operationsClient.cancelOperation(
-          request,
-          undefined,
-          (
-            err?: Error | null,
-            result?: protos.google.protobuf.Empty | null
-          ) => {
-            if (err) {
-              reject(err);
-            } else {
-              resolve(result);
-            }
-          }
-        );
-      });
-      const response = await promise;
-      assert.deepStrictEqual(response, expectedResponse);
-      assert((client.operationsClient.cancelOperation as SinonStub).getCall(0));
-    });
-    it('invokes cancelOperation with error', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.CancelOperationRequest()
-      );
-      const expectedError = new Error('expected');
-      client.operationsClient.cancelOperation = stubSimpleCall(
-        undefined,
-        expectedError
-      );
-      await assert.rejects(async () => {
-        await client.cancelOperation(request);
-      }, expectedError);
-      assert(
-        (client.operationsClient.cancelOperation as SinonStub)
-          .getCall(0)
-          .calledWith(request)
-      );
-    });
-  });
-  describe('deleteOperation', () => {
-    it('invokes deleteOperation without error', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      client.initialize();
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.DeleteOperationRequest()
-      );
-      const expectedResponse = generateSampleMessage(
-        new protos.google.protobuf.Empty()
-      );
-      client.operationsClient.deleteOperation =
-        stubSimpleCall(expectedResponse);
-      const response = await client.deleteOperation(request);
-      assert.deepStrictEqual(response, [expectedResponse]);
-      assert(
-        (client.operationsClient.deleteOperation as SinonStub)
-          .getCall(0)
-          .calledWith(request)
-      );
-    });
-    it('invokes deleteOperation without error using callback', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.DeleteOperationRequest()
-      );
-      const expectedResponse = generateSampleMessage(
-        new protos.google.protobuf.Empty()
-      );
-      client.operationsClient.deleteOperation = sinon
-        .stub()
-        .callsArgWith(2, null, expectedResponse);
-      const promise = new Promise((resolve, reject) => {
-        client.operationsClient.deleteOperation(
-          request,
-          undefined,
-          (
-            err?: Error | null,
-            result?: protos.google.protobuf.Empty | null
-          ) => {
-            if (err) {
-              reject(err);
-            } else {
-              resolve(result);
-            }
-          }
-        );
-      });
-      const response = await promise;
-      assert.deepStrictEqual(response, expectedResponse);
-      assert((client.operationsClient.deleteOperation as SinonStub).getCall(0));
-    });
-    it('invokes deleteOperation with error', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.DeleteOperationRequest()
-      );
-      const expectedError = new Error('expected');
-      client.operationsClient.deleteOperation = stubSimpleCall(
-        undefined,
-        expectedError
-      );
-      await assert.rejects(async () => {
-        await client.deleteOperation(request);
-      }, expectedError);
-      assert(
-        (client.operationsClient.deleteOperation as SinonStub)
+        )
           .getCall(0)
-          .calledWith(request)
-      );
-    });
-  });
-  describe('listOperationsAsync', () => {
-    it('uses async iteration with listOperations without error', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.ListOperationsRequest()
-      );
-      const expectedResponse = [
-        generateSampleMessage(
-          new operationsProtos.google.longrunning.ListOperationsResponse()
-        ),
-        generateSampleMessage(
-          new operationsProtos.google.longrunning.ListOperationsResponse()
-        ),
-        generateSampleMessage(
-          new operationsProtos.google.longrunning.ListOperationsResponse()
-        ),
-      ];
-      client.operationsClient.descriptor.listOperations.asyncIterate =
-        stubAsyncIterationCall(expectedResponse);
-      const responses: operationsProtos.google.longrunning.ListOperationsResponse[] =
-        [];
-      const iterable = client.operationsClient.listOperationsAsync(request);
-      for await (const resource of iterable) {
-        responses.push(resource!);
-      }
-      assert.deepStrictEqual(responses, expectedResponse);
-      assert.deepStrictEqual(
-        (
-          client.operationsClient.descriptor.listOperations
-            .asyncIterate as SinonStub
-        ).getCall(0).args[1],
-        request
-      );
-    });
-    it('uses async iteration with listOperations with error', async () => {
-      const client = new registryModule.v1.RegistryClient({
-        credentials: {client_email: 'bogus', private_key: 'bogus'},
-        projectId: 'bogus',
-      });
-      client.initialize();
-      const request = generateSampleMessage(
-        new operationsProtos.google.longrunning.ListOperationsRequest()
-      );
-      const expectedError = new Error('expected');
-      client.operationsClient.descriptor.listOperations.asyncIterate =
-        stubAsyncIterationCall(undefined, expectedError);
-      const iterable = client.operationsClient.listOperationsAsync(request);
-      await assert.rejects(async () => {
-        const responses: operationsProtos.google.longrunning.ListOperationsResponse[] =
-          [];
-        for await (const resource of iterable) {
-          responses.push(resource!);
-        }
-      });
-      assert.deepStrictEqual(
-        (
-          client.operationsClient.descriptor.listOperations
-            .asyncIterate as SinonStub
-        ).getCall(0).args[1],
-        request
+          .args[2].otherArgs.headers['x-goog-request-params'].includes(
+            expectedHeaderRequestParams
+          )
       );
     });
   });