diff --git a/libs/prebuilt/langgraph/prebuilt/tool_node.py b/libs/prebuilt/langgraph/prebuilt/tool_node.py
index 3ef074e54..0f7621bec 100644
--- a/libs/prebuilt/langgraph/prebuilt/tool_node.py
+++ b/libs/prebuilt/langgraph/prebuilt/tool_node.py
@@ -399,7 +399,7 @@ class ToolNode(RunnableCallable):
                 )
             
             # Check for reserved keywords and wrap the tool if needed
-            reserved_args = _get_reserved_keyword_args(tool_)
+            # (already computed above, no need to recompute)
             if reserved_args:
                 tool_ = _wrap_tool_with_reserved_keywords(tool_, reserved_args)
             
@@ -1393,5 +1393,6 @@ def _get_runtime_arg(tool: BaseTool) -> Optional[str]:
 
 
 
+