Add tool_calls in AIMessage (#1314)

Author: nicolasse

langfuse/langchain/CallbackHandler.py

@@ -912,6 +912,13 @@ def _convert_message_to_dict(self, message: BaseMessage) -> Dict[str, Any]:
             message_dict = {"role": "user", "content": message.content}
         elif isinstance(message, AIMessage):
             message_dict = {"role": "assistant", "content": message.content}
+
+            if (
+                hasattr(message, "tool_calls")
+                and message.tool_calls is not None
+                and len(message.tool_calls) > 0
+            ):
+                message_dict["tool_calls"] = message.tool_calls
         elif isinstance(message, SystemMessage):
             message_dict = {"role": "system", "content": message.content}
         elif isinstance(message, ToolMessage):