/web-browser

name: web-browser
description: "Automate and interact with web pages through Chrome or Chromium using the Chrome DevTools Protocol (CDP): navigate, click, fill forms, inspect content, take screenshots, and debug console or network activity. Use when an agent needs a real browser. Prefer headless Chrome unless visible browser interaction is required."
license: Stolen from Mario

Web Browser Skill

Minimal CDP tools for collaborative site exploration.

Start Chrome (Prefer Headless)

./scripts/start.js --headless            # Recommended: isolated reusable profile
./scripts/start.js --headless --profile  # Headless with a copy of your profile
./scripts/start.js                       # Visible browser window when needed
./scripts/start.js --headless --reset-profile  # Clear cached profile before launch

Starts Chrome with remote debugging (default port `:9222`). **Agents should use `--headless` by default** because it is less disruptive and supports navigation, evaluation, screenshots, emulation, and logging. User extensions are disabled for headless launches; a copied profile still provides its cookies and other browser state, but extension-based features are unavailable. Headed launches continue to load extensions normally. Use headed mode only when a person needs to see or interact with the browser, such as for `pick.js`, manual authentication, or debugging a headless-specific difference.

The start script only reuses a running browser when its profile and launch settings match. Stop the running skill browser before switching between headless and headed mode. Changing the debugging port does **not** isolate the profile: startup refuses to modify a profile already used on another port and preserves Chrome's profile locks.

Profile behavior:

• Default mode uses: `~/.cache/agent-web/browser/fresh-profile`
• `--profile` mode uses: `~/.cache/agent-web/browser/profile-copy`
• The skill **does not attach to your live Chrome profile directly**
• If `:9222` is already used by an unknown instance, start will fail instead of reusing it

If Chrome is installed in a non-standard location, set:

BROWSER_BIN=/path/to/chrome ./scripts/start.js --headless

Optional debug endpoint override:

BROWSER_DEBUG_PORT=9333 ./scripts/start.js --headless

Stop Chrome

./scripts/stop.js                         # Stop skill Chrome on :9222
BROWSER_DEBUG_PORT=9333 ./scripts/stop.js  # Stop skill Chrome on :9333
./scripts/stop.js --all                   # Stop all skill Chrome instances

Works for headless and headed browsers. Only processes using the skill's cached profiles are stopped, not your regular Chrome. Shutdown preserves cookies and other cached state; it never force-kills Chrome. Stop before using `--reset-profile`.

To switch to a visible browser:

./scripts/stop.js
./scripts/start.js

Navigate

./scripts/nav.js https://example.com
./scripts/nav.js https://example.com --new

Navigate current tab or open new tab.

Device Emulation (Mobile)

./scripts/emulate.js --list
./scripts/emulate.js iphone-14
./scripts/emulate.js pixel-7 --landscape
./scripts/emulate.js --reset

Set an active device emulation preference (viewport, DPR, touch, UA) for browser skill commands. Use `--reset` to clear.

Commands like `nav.js`, `eval.js`, `pick.js`, `dismiss-cookies.js`, and `screenshot.js` automatically apply the active preference.

Evaluate JavaScript

./scripts/eval.js 'document.title'
./scripts/eval.js 'document.querySelectorAll("a").length'
./scripts/eval.js 'document.querySelector("button")?.click(); "clicked"'
./scripts/eval.js 'await Promise.resolve(document.title)'
./scripts/eval.js 'JSON.stringify(Array.from(document.querySelectorAll("a")).map(a => ({ text: a.textContent.trim(), href: a.href })).filter(link => !link.href.startsWith("https://")))'

Execute JavaScript in the active tab. Input can be an expression or statement list; the console-style completion value is printed and promises/top-level `await` are awaited. Be careful with string escaping, best to use single quotes.

Screenshot

./scripts/screenshot.js
./scripts/screenshot.js --full-page
./scripts/screenshot.js --device iphone-14
./scripts/screenshot.js --device pixel-7 --full-page

Takes a screenshot and returns a temp file path.

• Default: current viewport
• `--full-page`: captures full document height
• `--device <preset>`: temporary mobile emulation for that screenshot only

Pick Elements

./scripts/pick.js "Click the submit button"

Interactive element picker. Click to select, Cmd/Ctrl+Click for multi-select, Enter to finish. This requires headed Chrome; launch `start.js` without `--headless`.

Dismiss Cookie Dialogs

./scripts/dismiss-cookies.js          # Accept cookies
./scripts/dismiss-cookies.js --reject # Reject cookies (where possible)

Automatically dismisses EU cookie consent dialogs.

Run after navigating to a page:

./scripts/nav.js https://example.com && ./scripts/dismiss-cookies.js

Quick Mobile Debug Flow

./scripts/start.js --headless
./scripts/nav.js https://example.com
./scripts/emulate.js iphone-14
./scripts/nav.js https://example.com      # reload with mobile UA
./scripts/dismiss-cookies.js
./scripts/screenshot.js --full-page

Background Logging (Console + Errors + Network)

Automatically started by `start.js` and writes JSONL logs to:

~/.cache/agent-web/logs/YYYY-MM-DD/<targetId>.jsonl

Manually start:

./scripts/watch.js

Tail latest log:

./scripts/logs-tail.js           # dump current log and exit
./scripts/logs-tail.js --follow  # keep following

Summarize network responses:

./scripts/net-summary.js