diff --git a/libs/langgraph/langgraph/pregel/__init__.py b/libs/langgraph/langgraph/pregel/__init__.py
index 33bae3330..79f7afa05 100644
--- a/libs/langgraph/langgraph/pregel/__init__.py
+++ b/libs/langgraph/langgraph/pregel/__init__.py
@@ -189,7 +189,7 @@ def _get_checkpoint_ns_to_graph(
 
     if max_depth <= 0:
         raise RecursionError(
-            f"Reached maximum recursion depth while building checkpoint NS -> graph mapping."
+            "Reached maximum recursion depth while building checkpoint NS -> graph mapping."
         )
 
     for node_name, node in graph.nodes.items():