diff --git a/libs/partners/openai/langchain_openai/chat_models/base.py b/libs/partners/openai/langchain_openai/chat_models/base.py
index bd25249f8b8..070e2e1bd36 100644
--- a/libs/partners/openai/langchain_openai/chat_models/base.py
+++ b/libs/partners/openai/langchain_openai/chat_models/base.py
@@ -219,6 +219,11 @@ def _convert_message_to_dict(message: BaseMessage) -> dict:
         message_dict["role"] = "tool"
         message_dict["tool_call_id"] = message.tool_call_id
 
+        # Note: "name" is not documented in OpenAI's API Reference
+        # https://platform.openai.com/docs/api-reference/chat/create
+        # but is referenced in cookbooks
+        # https://cookbook.openai.com/examples/how_to_call_functions_with_chat_models
+        # and is required for some proxys (e.g., Google Gemini).
         supported_props = {"content", "role", "tool_call_id", "name"}
         message_dict = {k: v for k, v in message_dict.items() if k in supported_props}
     else: