xavieluh/mern-openai-chatbot ? reverse-engineered prompt

Build me a simple AI chat app with a React front end and a small Express backend.

I want a clean chat screen where I can type a message, press Enter or click send, and see my message plus the assistant reply in a conversation thread. While the app is waiting for the AI response, show a typing or loading state and disable the send button so it feels responsive.

The backend should accept a message from the browser, keep the conversation history on the server for now, send the full chat context to OpenAI, and return the assistant response back to the UI. It’s okay if this is a basic shared session prototype for now, but please make the chat flow smooth and working end to end.

Use current docs online if you need to, and make sure the app runs locally with a separate frontend and backend setup.