update

app.py

@@ -26,6 +26,14 @@ calculator_agent = ReActAgent(
     llm=llm,
 )
 
+query_engine = index.as_query_engine(llm=llm)
+query_engine_tool = QueryEngineTool.from_defaults(
+    query_engine=query_engine,
+    name="personas",
+    description="descriptions for various types of personas",
+    return_direct=False,
+)
+
 query_agent = ReActAgent(
     name="query_agent",
     description="A query agent that can query the internet.",