diff --git a/libs/core/langchain_core/tools/retriever.py b/libs/core/langchain_core/tools/retriever.py
index 23b4af29593bd..7d0abaacfa495 100644
--- a/libs/core/langchain_core/tools/retriever.py
+++ b/libs/core/langchain_core/tools/retriever.py
@@ -103,5 +103,5 @@ def create_retriever_tool(
         func=func,
         coroutine=afunc,
         args_schema=RetrieverInput,
-        response_format=response_format
+        response_format=response_format,
     )