Update lg_chat_agent.py

lg_chat_agent.py

@@ -1,23 +1,27 @@
 from llm import llm
-from langgraph.graph import MessagesState, START, StateGraph
-from langchain_core.messages import HumanMessage
+from langgraph.graph import MessagesState, START, END, StateGraph
+from langchain_core.messages import HumanMessage, AIMessage
 
 def bot(state: MessagesState):
-    messages = state["messages"]
-    response = llm.invoke(messages)
-    return {"messages": [response]}
+    user_message = state["messages"][-1].content
+
+    response = llm.invoke(user_message)
+
+    return {
+        "messages": [AIMessage(content=response.content)]
+    }
 
 builder = StateGraph(MessagesState)
+
 builder.add_node("bot", bot)
 builder.add_edge(START, "bot")
+builder.add_edge("bot", END)  # ✅ REQUIRED
+
 graph = builder.compile()
 
 def chat_response(user_message: str) -> str:
-    final_response = None
-
-    for event in graph.stream(
+    result = graph.invoke(
         {"messages": [HumanMessage(content=user_message)]}
-    ):
-        final_response = event["bot"]["messages"][-1]
+    )
 
-    return final_response.content
+    return result["messages"][-1].content