diff --git a/docs/site/content/en/openapi/openapi.yaml b/docs/site/content/en/openapi/openapi.yaml
index 957f362e7..cda16ca0c 100644
--- a/docs/site/content/en/openapi/openapi.yaml
+++ b/docs/site/content/en/openapi/openapi.yaml
@@ -1551,7 +1551,8 @@ paths:
     post:
       tags:
       - Schema
-      description: Save new or update existing Label for a Schema
+      description: Save new or update existing Label for a Schema (Label id only required
+        when updating existing one)
       operationId: addOrUpdateLabel
       parameters:
       - name: schemaId
diff --git a/horreum-api/src/main/java/io/hyperfoil/tools/horreum/api/services/SchemaService.java b/horreum-api/src/main/java/io/hyperfoil/tools/horreum/api/services/SchemaService.java
index 925b8147f..1a6c260fa 100644
--- a/horreum-api/src/main/java/io/hyperfoil/tools/horreum/api/services/SchemaService.java
+++ b/horreum-api/src/main/java/io/hyperfoil/tools/horreum/api/services/SchemaService.java
@@ -168,7 +168,7 @@ int addOrUpdateTransformer(@PathParam("schemaId") int schemaId,
     @POST
     @Path("{schemaId}/labels")
     @Consumes(MediaType.APPLICATION_JSON)
-    @Operation(description = "Save new or update existing Label for a Schema")
+    @Operation(description = "Save new or update existing Label for a Schema (Label id only required when updating existing one)")
     @Parameters(value = {
             @Parameter(name = "schemaId", description = "Schema ID", example = "101"),
     })