# Describe a web app and review the prototype

> Claude Duet can prototype a web app on its cloud computer from a description you write. You review the files in the Make tab. You cannot watch the browser.

Language: English
Page: https://duetcases.com/coding/prototype-web-app
Source: Introducing Claude Duet — https://claude.com/resources/articles/claude-duet

## What this does

Claude Duet can prototype a web app on its own cloud computer from a description you give it, and leave the files for you in the Make tab. You cannot watch its browser, point it at a folder on your laptop, or pick a different model. It runs on Claude Opus 5.5.

## Problem

A prototype starts as a description: who it is for, and the one thing it should do. The rest is files you still have to read.

The [launch article](https://claude.com/resources/articles/claude-duet) says Claude Duet can prototype and build web apps on a computer in the cloud, including while your laptop is off. The [help center](https://support.claude.com/en/articles/17631495-get-started-with-claude-duet) adds the limits that decide whether this is useful. You cannot watch the browser. It cannot see files on your computer, and it cannot change work already in Claude. Finished files are for the Make tab. The preview runs on Claude Opus 5.5, with no model picker. A password goes to the browser, not the chat.

Anthropic names prototyping. It does not publish a how-to for a specific framework, so this case does not invent one. Staff anecdotes about shipping code are Anthropic’s own stories, not a result this template promises. Deleting anything still waits for your approval, and a larger build draws more of your plan limits.

## Steps

1. Write a short description: who uses the app, the one job it does, and what “done” looks like on a screen. Anthropic says Claude Duet can prototype and build web apps. It does not publish a framework-by-framework guide.
2. Paste the prompt. Claude Duet works on a cloud computer. Your laptop can be closed. You cannot watch the browser it uses.
3. Review the files in the Make tab. The help center says finished files land there. It also says Claude Duet cannot see the files on your computer, and cannot change your existing Claude work.
4. There is no model picker. The help center says the research preview runs on Claude Opus 5.5.
5. A prototype is a larger job. It counts toward the same plan limits. If a step would delete something, Claude Duet is designed to wait for approval.

## Prompt

```
Prototype a small web app from the description I give next. Work on your cloud computer. Do not look for a folder on my laptop, and do not ask me to watch the browser — I cannot see it. When you have something I can review, put the files in the Make tab and tell me what the app does, what you assumed, and what is still missing. Do not claim a specific framework unless I named one. Wait before you delete anything.

```

## When to use

- You can describe the app in words and you want a first version to react to.
- You do not need to watch the work happen, and you do not need it pointed at a local repo.
- You accept that Anthropic has not published a stack-specific how-to for this.

## FAQ

### What does Anthropic say about coding?

The launch article and the help center say Claude Duet can prototype and build web apps, and that it works on its own computer in the cloud. They do not publish a guide for a named framework.

### Can I watch it browse?

No. The help center says you cannot watch its browser. A password you give it goes to that browser, not into the chat.

### Can I choose the model?

No. During the research preview, Claude Duet runs on Claude Opus 5.5 and there is no model picker.