diff --git a/pinecone/openapi_support/api_client.py b/pinecone/openapi_support/api_client.py
index afd6b96c..c716a248 100644
--- a/pinecone/openapi_support/api_client.py
+++ b/pinecone/openapi_support/api_client.py
@@ -212,9 +212,11 @@ def __call_api(
                 response_info = extract_response_info(headers)
                 if isinstance(return_data, dict):
                     return_data["_response_info"] = response_info
-                else:
+                elif hasattr(return_data, "__dict__"):
                     # Dynamic attribute assignment on OpenAPI models
                     setattr(return_data, "_response_info", response_info)
+                # Primitive types (str, int, float, bool) do not support
+                # attribute assignment, so response_info is silently skipped.
 
         if _return_http_data_only:
             return return_data
diff --git a/pinecone/openapi_support/asyncio_api_client.py b/pinecone/openapi_support/asyncio_api_client.py
index 58a3a869..fa03e770 100644
--- a/pinecone/openapi_support/asyncio_api_client.py
+++ b/pinecone/openapi_support/asyncio_api_client.py
@@ -177,9 +177,11 @@ async def __call_api(
                 response_info = extract_response_info(headers)
                 if isinstance(return_data, dict):
                     return_data["_response_info"] = response_info
-                else:
+                elif hasattr(return_data, "__dict__"):
                     # Dynamic attribute assignment on OpenAPI models
                     setattr(return_data, "_response_info", response_info)
+                # Primitive types (str, int, float, bool) do not support
+                # attribute assignment, so response_info is silently skipped.
 
         if _return_http_data_only:
             return return_data