updated agent

app.py

@@ -29,6 +29,9 @@ class BasicAgent:
         messages = [HumanMessage(content=question)]
         messages = self.graph.invoke({"messages": messages})
         print("message",messages)
+        if not messages or "messages" not in messages or not messages["messages"]:
+            print("⚠️ No messages returned by the graph.")
+            return "ERROR: Agent did not return a response."
         answer = messages['messages']  #[-1].content
         print(answer)
         return answer[14:]