diff --git a/libs/partners/openai/langchain_openai/chat_models/base.py b/libs/partners/openai/langchain_openai/chat_models/base.py
index 42b2501cbbfa6..b31742a4e10fb 100644
--- a/libs/partners/openai/langchain_openai/chat_models/base.py
+++ b/libs/partners/openai/langchain_openai/chat_models/base.py
@@ -2486,7 +2486,7 @@ def _oai_structured_outputs_parser(ai_msg: AIMessage) -> PydanticBaseModel:
     else:
         raise ValueError(
             "Structured Output response does not have a 'parsed' field nor a 'refusal' "
-            "field. Received message:\n\n{ai_msg}"
+            f"field. Received message:\n\n{ai_msg}"
         )