diff --git a/libs/langchain/langchain/output_parsers/openai_tools.py b/libs/langchain/langchain/output_parsers/openai_tools.py
index bea4b12a3c2..39fd05974a9 100644
--- a/libs/langchain/langchain/output_parsers/openai_tools.py
+++ b/libs/langchain/langchain/output_parsers/openai_tools.py
@@ -72,6 +72,10 @@ class JsonOutputKeyToolsParser(JsonOutputToolsParser):
     return_single: bool = False
     """Whether to return only the first tool call."""
 
+    def __init__(self, key_name: str, **kwargs: Any) -> None:
+        """Allow init with positional args."""
+        super().__init__(key_name=key_name, **kwargs)
+
     def parse_result(self, result: List[Generation], *, partial: bool = False) -> Any:
         results = super().parse_result(result)
         results = [res for res in results if res["type"] == self.key_name]