Updating message callback

app.py

@@ -256,6 +256,8 @@ async def main(message: cl.Message):
     for chunk in agent.stream(
         {"messages": HumanMessage(content="Can you compare the most recent financial reports of Microsoft and Nvidia?")},
     ):
-        await msg.stream_token(chunk)
+        for key in chunk:
+            if key == "agent" and chunk[key].get("messages")[0].content is not None:
+                await msg.stream_token(chunk[key].get("messages")[0].content)
 
     await msg.send()