Update LG_agent.py

LG_agent.py

@@ -10,16 +10,9 @@ import os
 # 1. Setup once
 chat = ChatOpenAI(
     model="gpt-3.5-turbo",
-    openai_api_key=os.getenv("OPENAI_API_KEY"),
+    openai_api_key=OPENAI_API_KEY,
     temperature=0,
-    model_kwargs={
-        "system_message": (
-            "You are a step-by-step reasoning assistant. "
-            "Always think out loud, use available tools when appropriate, and aim for factual, complete answers."
-        )
-    }
 )
-
 chat_with_tools = chat.bind_tools(all_tools)
 
 # 2. Define the agent state