Chainlit/chainlit ? reverse-engineered prompt

Build me a Python app for conversational AI that opens in the browser and feels polished enough to use right away.

I want a simple chat interface where a user can type a message, get a response back, and see intermediate updates when the app is doing work, like calling a tool or waiting on an AI model. Please make it easy to connect to common LLM setups later, and include a small starter example so I can run it locally and see it working immediately.

It should be the kind of thing I can launch with one command, then edit a single Python file to define how messages are handled. If you need current docs or examples for any recent libraries, look them up online. Keep the first version focused on the core chat experience, clean UI, and a good developer experience for building conversational apps fast.