load model lazily in expert tool to avoid model instantiation when module is imported

ra_aid/tools/expert.py

@@ -8,7 +8,13 @@ from langchain_openai import ChatOpenAI
 from .memory import get_memory_value, get_related_files
 
 console = Console()
-model = ChatOpenAI(model_name="o1-preview")
+_model = None
+
+def get_model():
+    global _model
+    if _model is None:
+        _model = ChatOpenAI(model_name="o1-preview")
+    return _model
 
 # Keep track of context globally
 expert_context = []
@@ -168,7 +174,7 @@ def ask_expert(question: str) -> str:
         query = "\n".join(query_parts)
         
     # Get response
-    response = model.invoke(query)
+    response = get_model().invoke(query)
     
     # Format and display response
     console.print(Panel(