browser-cdp

name: browser-cdp description: "Control a browser via Chrome DevTools Protocol (CDP) proxy. Use when: (1) navigating to URLs and reading page content, (2) taking screenshots, (3) executing JavaScript in the browser, (4) clicking elements or filling forms, (5) searching and installing Chrome Web Store extensions, (6) interacting with web APIs that require a real browser. NOT for: simple HTTP requests (use curl), local file operations, or when no CDP proxy is available." metadata: { "openclaw": { "emoji": "🌐", "requires": { "bins": ["curl"] } }

}

Browser CDP

Control a real browser through a Chrome DevTools Protocol proxy.

Overview

This skill provides browser automation via a lightweight HTTP proxy that wraps CDP. The proxy exposes REST endpoints for navigation, screenshots, JS evaluation, clicking, and more — no Playwright/Puppeteer dependency needed.

Prerequisites

Install the required Python dependency:

pip install psutil

A CDP proxy must be running on http://localhost:3456. Start it from the repository root with:

python3 skills/browser-cdp/scripts/cdp_proxy.py

This launches Chrome/Edge with remote debugging enabled and proxies CDP commands over HTTP.

When to Use

✅ USE this skill when:

• "Open this URL and tell me what's on the page"
• "Take a screenshot of the current page"
• "Run this JavaScript on the page"
• "Click the button that says..."
• "Search for and install a Chrome extension"
• "Log into this site and do something"
• Any task requiring a real browser context

❌ DON'T use this skill when:

• Simple HTTP API calls → use curl directly
• Downloading files → use curl -O
• Parsing HTML from a saved file → use python3 with BeautifulSoup
• No CDP proxy running → ask the user to start it first

API Reference

All endpoints are relative to http://localhost:3456.

GET /targets

List all open browser tabs.

curl -s http://localhost:3456/targets | python3 -m json.tool

Response:

[
  { "id": "ABC123", "title": "Google", "url": "https://google.com" }
]

GET /navigate?url=

Navigate a tab to a URL. Uses the most recently created tab, or specify ?target=<targetId>.

curl -s "http://localhost:3456/navigate?url=https://example.com"

GET /screenshot

Take a PNG screenshot of the current page.

# Save to file
curl -s -o screenshot.png http://localhost:3456/screenshot

POST /eval

Execute JavaScript in the page. The request body is plain text (not JSON), sent as Content-Type: text/plain.

curl -s -X POST http://localhost:3456/eval \
  -H "Content-Type: text/plain" \
  -d "document.title"

For multi-line scripts, pipe from stdin or use a heredoc:

curl -s -X POST http://localhost:3456/eval \
  -H "Content-Type: text/plain" \
  -d "JSON.stringify(Array.from(document.querySelectorAll('a')).map(a => ({text: a.innerText, href: a.href})))"

GET /click?selector=

Click an element matching a CSS selector.

curl -s "http://localhost:3456/click?selector=%23submit-btn"

GET /new

Open a new browser tab and return its target ID.

curl -s http://localhost:3456/new

Response:

{ "id": "NEW_TAB_ID", "title": "about:blank", "url": "about:blank" }

Common Workflows

Navigate and extract page content

# Open a page
curl -s "http://localhost:3456/navigate?url=https://example.com"

# Extract all text content
curl -s -X POST http://localhost:3456/eval \
  -H "Content-Type: text/plain" \
  -d "document.body.innerText"

# Extract all links
curl -s -X POST http://localhost:3456/eval \
  -H "Content-Type: text/plain" \
  -d "JSON.stringify([...document.querySelectorAll('a')].map(a => ({text: a.textContent.trim(), href: a.href})))"

Take a screenshot

curl -s "http://localhost:3456/navigate?url=https://example.com"
curl -s -o page.png http://localhost:3456/screenshot

Search and install a Chrome extension

# Search the Chrome Web Store (no login required for search)
curl -s "http://localhost:3456/navigate?url=https://chromewebstore.google.com/search/example%20extension"

# Extract extension IDs from search results
curl -s -X POST http://localhost:3456/eval \
  -H "Content-Type: text/plain" \
  -d "JSON.stringify([...document.querySelectorAll('a[data-id]')].map(a => ({id: a.dataset.id, title: a.textContent.trim()})))"

# Install an extension (requires the extension ID)
curl -s "http://localhost:3456/navigate?url=https://chromewebstore.google.com/detail/<extension-id>"
# Then click the "Add to Chrome" button
curl -s "http://localhost:3456/click?selector=%5Bdata-id%3Dinstall-button%5D"

Fill a form and submit

# Navigate to the form
curl -s "http://localhost:3456/navigate?url=https://example.com/login"

# Fill in fields
curl -s -X POST http://localhost:3456/eval \
  -H "Content-Type: text/plain" \
  -d "document.querySelector('#username').value = 'myuser'"
curl -s -X POST http://localhost:3456/eval \
  -H "Content-Type: text/plain" \
  -d "document.querySelector('#password').value = 'mypass'"

# Submit
curl -s "http://localhost:3456/click?selector=%23login-form+%3E+button"

Notes

• The CDP proxy must be running before using any commands
• If the proxy is not running, ask the user to start it: python3 skills/browser-cdp/scripts/cdp_proxy.py
• Use URL encoding for query parameters with special characters
• The /eval endpoint returns the result of the last expression (like a REPL)
• Screenshots are returned as PNG binary data
• For complex multi-step interactions, chain /eval and /click calls
• The proxy supports a ?target=<targetId> parameter on most endpoints to target a specific tab