diff --git a/lib/blocks/jsdebug.js b/lib/blocks/jsdebug.js
index 2fd3b9f..8c173f7 100644
--- a/lib/blocks/jsdebug.js
+++ b/lib/blocks/jsdebug.js
@@ -390,7 +390,7 @@ function checkArgsTypes(method, args) {
   var params = method.params;
   var maxOptionals = params.length - (params.length - getOptionalParamsCount(method.params));
   var paramIndex = 0;
-  var passDetailValues = blocks.queries[method.name].passDetailValues;
+  var passDetailValues = blocks.queries[method.name] && blocks.queries[method.name].passDetailValues;
   var currentErrors;
   var param;
   var value;