Update app.py

app.py

@@ -63,6 +63,8 @@ def run_conversation(user_prompt, messages, model_option, max_tokens):
 
         for tool_call in tool_calls:
             function_name = tool_call.function.name
+            if function_name not in available_functions:
+                return "Invalid tool provided."
             function_to_call = available_functions[function_name]
             function_args = json.loads(tool_call.function.arguments)
             function_response = function_to_call(**function_args)