Update app.py

app.py

@@ -1,17 +1,28 @@
 import os
 import gradio as gr
-from openai import OpenAI
 
-# Initialize client with Hugging Face OpenAI-compatible endpoint
-client = OpenAI(
-    base_url="https://router.huggingface.co/v1",
-    api_key=os.environ["HF_TOKEN"],  # Hugging Face token stored in Secrets
-)
+try:
+    from openai import OpenAI
+except ImportError:
+    raise RuntimeError("⚠️ Missing dependency. Make sure 'openai' is listed in requirements.txt")
 
-# Function to handle chat conversation
+# Check if HF_TOKEN exists
+api_key = os.getenv("HF_TOKEN")
+
+client = None
+if api_key:
+    client = OpenAI(
+        base_url="https://router.huggingface.co/v1",
+        api_key=api_key,
+    )
+
+# Function to handle chat
 def chat_with_deepseek(message, history):
+    if not client:
+        return "❌ HF_TOKEN not found. Please set it in 'Settings → Repository secrets' of your Space."
+
     try:
-        # Convert Gradio history into OpenAI format
+        # Convert Gradio history to OpenAI messages format
         messages = []
         for user_msg, bot_msg in history:
             messages.append({"role": "user", "content": user_msg})
@@ -75,7 +86,7 @@ with gr.Blocks(theme="soft", css="""
     )
     submit_btn = gr.Button("Send", elem_id="submitbtn")
 
-    # Event: when user submits input
+    # Bind events
     submit_btn.click(
         fn=chat_with_deepseek,
         inputs=[user_input, chatbot],