Update app.py

app.py

@@ -1,11 +1,11 @@
 import streamlit as st
-from graph import EssayWriter, RouteQuery, GraphState
+from graph import EssayWriter
 import os
 import base64
 
 st.set_page_config(page_title="Multi-Agent Essay Writer", page_icon="🤖🤖🤖✍️")
 
-# Button HTML
+# Button HTML (for external links)
 button_html = f'''
     <div style="display: flex; justify-content: center;">
         <a href=" " target="_blank">
@@ -41,7 +41,7 @@ with st.sidebar:
         "\n\n* This app uses the 'gpt-4o-mini-2024-07-18' model."
         "\n\n* Writing essays may take some time, approximately 1-2 minutes."
     )
-    
+
     openai_key = st.secrets.get("OPENAI_API_KEY", "")
 
     st.divider()
@@ -66,8 +66,8 @@ def initialize_agents():
             return st.session_state.app  # Prevent re-initialization
         
         essay_writer = EssayWriter().graph
-        st.success("Agents successfully initialized!")
         st.session_state.chat_active = False
+        st.success("Agents successfully initialized!")
         return essay_writer
     except Exception as e:
         st.error(f"Error initializing agents: {e}")
@@ -78,11 +78,18 @@ def initialize_agents():
 if "app" not in st.session_state or st.session_state.app is None:
     st.session_state.app = initialize_agents()
 
+if st.session_state.app is None:
+    st.error("Failed to initialize agents. Please check your API key and restart the app.")
+
 app = st.session_state.app  
 
 # Function to invoke the agent and generate a response
 def generate_response(topic):
-    return app.invoke(input={"topic": topic}) if app else {"response": "Error: Agents not initialized."}
+    if not app:
+        st.error("Agents are not initialized. Please check the system or restart the app.")
+        return {"response": "Error: Agents not initialized."}
+
+    return app.invoke(input={"topic": topic})
 
 # Display chat messages from the session
 for message in st.session_state.messages: