An AI agent that browses for you: Agent Browser

Tools: Agent Browser, Claude Code
Price: Free (Apache-2.0), plus your Claude plan
Time: 15 min
Level: Terminal, beginner

You update your website, then open the contact page, fill in the form with a fake name, submit it and check the confirmation page. Then you do it again on mobile. An AI agent can do this kind of repetitive check for you, as long as you give it a browser. That is exactly what Agent Browser does.

What it is for, and who it is for

Agent Browser is a command-line program built for AI agents. It drives a real Chrome browser and describes each page as a list of numbered elements (@e1, @e2…). The agent reads that list, picks an element, then clicks it or types into it. For an AI, this is more reliable than guessing coordinates on an image.

It is useful if you already use Claude Code (or another terminal agent) and want to hand it:

checks on your own website after a change (forms, links, layout);
screenshots of your pages for a client report;
repetitive data entry in a web tool you already use, on your own account.

Install Agent Browser

Install the programYou need Node.js (for the npm command). On a Mac, Homebrew works too: brew install agent-browser.
Terminal
```
npm install -g agent-browser
```
Download the browserThis command fetches Chrome for Testing, the build of Chrome that Google ships for automation. You only run it once.
Terminal
```
agent-browser install
```
Try it by handBefore handing the tool to Claude, run a test yourself. --headed shows the window so you can see what happens.
Terminal
```
agent-browser open example.com --headed
agent-browser snapshot
agent-browser screenshot test.png
agent-browser close
```
Teach it to Claude CodeIn the folder where you run Claude Code, add the official skill. It creates a small file in .claude/skills/agent-browser/ that tells Claude how to use the tool.
Terminal
```
npx skills add vercel-labs/agent-browser
```

Example: test your website's contact form

Start claude in the folder, then paste this prompt, replacing the address with your own site:

Prompt

Use agent-browser to check the contact form on my website.
1. Open https://www.my-site.com/contact in visible mode (--headed).
2. Fill in the form with this test data:
   name "Form test", email "[email protected]",
   message "Automated test, please ignore".
3. Submit it, wait for the next page and take a screenshot.
4. Tell me whether it worked and copy any error message word for word.
Stay on www.my-site.com only. Do not log in to any account.
Ask me before any action that is not on this list.

Claude then chains the open, snapshot, fill, click and screenshot commands, and shows you each one before running it if you are in the default permission mode. You watch the browser move and get the screenshot in the folder.

Useful settings

Limit the sites: --allowed-domains blocks navigation outside the listed domains, for example --allowed-domains "my-site.com,*.my-site.com".
Ask for confirmation: --confirm-actions requires your approval for some action categories, such as eval,download (running code in the page, downloading a file).
Separate page content: --content-boundaries wraps the text read from the page so the AI can tell what comes from the site apart from your instructions.
Separate sessions: --session client-a keeps cookies isolated from one task to the next.

These protections are off by default: you need to add them, or ask Claude to use them in your prompt.

Limits and cost

The tool is free. What costs money is Claude usage: every page read and every step uses part of your plan.
Pages change: after each navigation, the agent has to read the page again (a new snapshot). A cookie banner can block a click; it has to be closed first.
Captchas and sites that forbid bots are not what this is for. Respect each site's terms of use.

Be careful with logged-in accounts

Agent Browser can reuse a Chrome profile (--profile) or save a session to a file (state save). In practice, the agent then acts as you: it sees your emails and can send, buy or delete. The documentation also notes that these session files store login tokens in plain text.

Ground rules. Start with public pages or your own website, with no login. Never connect your bank or your main mailbox. If you save a session, keep the file out of any shared folder or GitHub and delete it when you are done. A web page can contain hidden instructions aimed at the AI: keep manual approvals on and review every sensitive action. And only install from the official vercel-labs/agent-browser repository.

Sources

Want an agent that does this every day, with guardrails that fit your business? That is what I build as AI agents.

An AI agent that browses, clicks and fills in your forms