Update app.py

app.py

@@ -43,13 +43,15 @@ with gr.Blocks() as demo:
         return "", history + [[user_message, None]]  # Add user message to chat history
 
     def bot(history):
-        user_message = history[-1][0]
-        payload = {
-            "inputs": user_message,
-            "parameters": {"function_call": "auto"}
-        }
-        output = query_model(payload)
-
+        if history:    
+            user_message = history[-1][0]
+            payload = {
+                "inputs": user_message,
+                "parameters": {"function_call": "auto"}
+            }
+            output = query_model(payload)
+        else:
+            return history  # Or some default response if history is empty
         # Parse the model's response
         if 'function_call' in output and 'name' in output['function_call']:
             function_name = output['function_call']['name']