ChromeBoost is a Chrome extension plus an MCP server. Together they let Claude Code drive the
browser sitting in front of you — the one with your sessions, your cookies, your logged-in
dashboards. You ask in plain English and watch it happen.

Anything irreversible stops and waits for you. Posts, payments, passwords and 2FA are yours
to confirm; ChromeBoost fills in everything around them and hands back control.

Things people actually say to it

"Reply to the new comments on my last LinkedIn post — draft each one and I'll hit Post."

Opens the post, reads the thread, types a reply into the composer for each comment. It stops at
Post every time: the button gets highlighted and it waits for your click, so nothing goes out in
your name that you didn't read.

"Grab my Stripe test keys and put them in .env"

Navigates to the dashboard you're already logged into, opens Developers → API keys, reveals the
secret, writes it straight to .env. The key never touches your clipboard.

"Walk through our signup flow and screenshot every step into ./docs"

Drives the flow like a new user — fills the form, submits, waits for each screen — saving a
numbered screenshot at every step. Onboarding docs that rebuild themselves.

"Drag the seat slider to 50 and tell me what it costs"

A slider has no button to click. ChromeBoost presses, moves through real intermediate positions,
releases, then reads the price back off the page.

"Download last month's invoices from the billing portal"

Signs in as you, filters the date range, pulls every PDF using your real session cookies — the
files a logged-out scraper can't reach.

Why it works where scripts don't

It doesn't teleport. A normal automation script jumps a cursor to coordinates and fires a
click event. ChromeBoost sends the whole gesture through Chrome's own input pipeline — a curved
approach, a settle tremor before it lands, pressure on the way down, keystrokes that arrive as
real key events. React, TipTap, ProseMirror, CodeMirror, Monaco and Stripe's contenteditable
fields all register input that scripted events silently swallow.

Cookie banners don't stop it. This is what breaks most browser agents: a page paints a scrim,
a modal backdrop, or an invisible catch-all <div> over the button, the click lands on that,
and the agent gets told it worked. It then argues with a button it never pressed. ChromeBoost
hit-tests the target first — aims at a part of it that's actually exposed, scrolls out from under
fixed bars, steps the overlay aside for the duration of a single click and puts it straight back.
When something genuinely can't be reached, it names the element in the way instead of claiming
success.

Not everything is click-shaped. hover for menus and row actions that only exist while the
pointer is on them. drag for sliders, canvas and WebGL apps, map panning, sortable lists,
resize handles.

Install

You need Chrome and Claude Code. There's nothing to clone and no build step — the plugin
ships both halves.

1. Add the plugin

In Claude Code, run these one at a time — not as a single paste:

/plugin marketplace add lordamdal/chromeboost

/plugin install chromeboost@chromeboost

Then restart Claude Code so the MCP server starts.

2. Load the extension

/chromeboost-setup

This copies the extension to ~/Downloads/ChromeBoost-Extension and opens the folder. It goes
to Downloads on purpose — the plugin's own directory is buried under ~/.claude/plugins/cache/…,
which is painful to reach in Chrome's folder picker and changes on every plugin update.

Then in Chrome:

1. Paste chrome://extensions into the address bar (chrome:// links can't be clicked).
2. Turn on Developer mode, top right.
3. Click Load unpacked and pick ChromeBoost-Extension — or drag the folder onto the page.

Leave that folder where it is. Chrome reads it on every launch, so moving or deleting it
breaks the extension. Chrome will also flag it as a developer-mode extension — expected, since
ChromeBoost isn't on the Web Store and runs from files you can read.

3. Point it at a window

Click the ChromeBoost icon in the toolbar. Your session appears with a green dot — hit Use this
window to bind the Chrome window you want driven. Then try:

open news.ycombinator.com and give me the top 5 stories

Using Gemini CLI instead?

ChromeBoost ships as a Gemini CLI extension too. The Chrome half is identical;
only the packaging differs.

gemini extensions install https://github.com/lordamdal/chromeboost

Restart Gemini, then run /chromeboost-setup exactly as above.

Gemini extension manifests cannot set trust, so if you want ChromeBoost's
tools to run without a confirmation each time, add it to ~/.gemini/settings.json:

{
  "mcpServers": {
    "chromeboost": { "trust": true }
  }
}

Worth understanding before you set that. trust: true runs every
ChromeBoost tool unprompted, including execute_script, which is arbitrary
JavaScript in whatever authenticated tab is active. trust: false (the
default) prompts instead, but in headless runs (gemini -p, piped stdin) a
prompt is treated as a denial, so long autonomous tasks fail partway.

For autonomy without the blanket switch, skip trust and use Gemini's policy
engine instead. See docs/gemini.md.

Using Codex instead?

Codex registers a command to run rather than fetching a package, so it needs a local
clone. This one paste does the whole thing, with no config file to hand-edit:

git clone https://github.com/lordamdal/chromeboost ~/.chromeboost/src \
  && npm --prefix ~/.chromeboost/src install \
  && npm --prefix ~/.chromeboost/src run build \
  && codex mcp add chromeboost --env CHROMEBOOST_HOST=codex \
       -- node ~/.chromeboost/src/packages/plugin/server/chromeboost.mjs

Restart Codex, then run /chromeboost-setup as above.

To update later:

git -C ~/.chromeboost/src pull && npm --prefix ~/.chromeboost/src run build

If something goes wrong

It wants the repo on its own, without the /plugin prefix:

lordamdal/chromeboost

owner/repo shorthand clones over SSH. Use the HTTPS URL instead:

https://github.com/lordamdal/chromeboost.git

Or set CLAUDE_CODE_PLUGIN_PREFER_HTTPS=1 to make shorthand clone over HTTPS.

The extension is loaded but hasn't connected. Hit the reload arrow on the ChromeBoost card in
chrome://extensions — it reconnects on a backoff timer, and a reload forces it immediately.

Run /chromeboost-setup again. It overwrites ~/Downloads/ChromeBoost-Extension in place, so you
only need to hit reload in chrome://extensions — no re-picking the folder.

git clone https://github.com/lordamdal/chromeboost
cd chromeboost
npm install
npm run build

Load packages/extension/dist unpacked, then
/plugin marketplace add /absolute/path/to/chromeboost.

To register the MCP server by hand instead of using the plugin:

{
  "mcpServers": {
    "chromeboost": {
      "command": "node",
      "args": ["/absolute/path/to/chromeboost/packages/plugin/server/chromeboost.mjs"]
    }
  }
}

You lose the bundled skill and permission allowlist, so you'll be prompted on every tool call.

The HUD

While Claude drives, a small panel sits on the page so you know a session is in control and which
one.

Position and state persist, so you only ever move it once. It lives in a closed shadow root — no
page can restyle it or find it — and only the panel itself takes clicks, never the space around
it. It's kept out of screenshots automatically.

Where it stops

An agent with your logins shouldn't be able to publish in your name, move your money, or pass
your 2FA on its own — and this one can't.

• Publishing — posts, comments and replies are drafted into the composer; the Post button is
  highlighted and waits for your real click.
• Passwords & 2FA — never typed. It brings you to the field and pauses. Secrets visible on
  screen are redacted out of what Claude reads by default.
• Payments & captchas — yours to confirm. Captchas aren't solved or faked; ChromeBoost
  reports one is present and steps back.

Tool surface

35 tools. You won't type any of them — Claude picks them — but here's what it can do:

Full agent-facing guide: packages/plugin/skills/chromeboost/SKILL.md.

Development

npm install
npm run build      # both halves; also syncs the extension into the plugin
npm run dev:ext    # extension, watch mode
npm run dev:mcp    # MCP server, tsc watch

Reload the extension at chrome://extensions after changing extension source. Restart Claude
Code after changing MCP server source.

CLAUDE.md is the repo-developer guide.

Support

ChromeBoost is free, MIT-licensed, and has no telemetry — the server only ever talks to your own
browser. If it saved you an afternoon:

☕ Buy me a coffee

License

MIT — see LICENSE.