diff --git a/src/google/adk/tools/openapi_tool/openapi_spec_parser/operation_parser.py b/src/google/adk/tools/openapi_tool/openapi_spec_parser/operation_parser.py
index 930e05c..ace4746 100644
--- a/src/google/adk/tools/openapi_tool/openapi_spec_parser/operation_parser.py
+++ b/src/google/adk/tools/openapi_tool/openapi_spec_parser/operation_parser.py
@@ -83,7 +83,8 @@ class OperationParser:
         schema.description = (
             description if not schema.description else schema.description
         )
-        required = param.required
+        # param.required can be None
+        required = param.required if param.required else False
 
         self.params.append(
             ApiParameter(