chrome-cdp-live-browser

$27

pi install git:github.com/pasky/chrome-cdp-skill@v1.0.1

Manual (for Amp, Claude Code, Cursor, Codex, etc.)

git clone https://github.com/pasky/chrome-cdp-skill

# Copy the skills/chrome-cdp/ directory to wherever your agent loads context from

Enable Remote Debugging in Chrome

• Open Chrome and navigate to: chrome://inspect/#remote-debugging

• Toggle the "Enable remote debugging" switch

That's all. No flags, no relaunching Chrome.

The script auto-detects Chrome, Chromium, Brave, Edge, and Vivaldi on macOS, Linux, and Windows. For non-standard installs:

export CDP_PORT_FILE=/path/to/DevToolsActivePort

Key Commands

All commands use scripts/cdp.mjs as the entry point. <target> is a unique prefix of the targetId shown by list.

List Open Tabs

node scripts/cdp.mjs list

# Output:

# A1B2C3  https://github.com/pasky/chrome-cdp-skill  chrome-cdp-skill

# D4E5F6  https://mail.google.com/mail/u/0/           Gmail

Screenshot a Tab

node scripts/cdp.mjs shot A1B2

# Saves screenshot to runtime dir, prints the file path

Accessibility Tree (Semantic Snapshot)

node scripts/cdp.mjs snap A1B2

# Returns compact, semantic accessibility tree — best for understanding page structure

Full HTML or Scoped HTML

node scripts/cdp.mjs html A1B2                    # full page HTML

node scripts/cdp.mjs html A1B2 ".main-content"    # scoped to CSS selector

node scripts/cdp.mjs html A1B2 "#article-body"    # scoped to ID

Evaluate JavaScript

node scripts/cdp.mjs eval A1B2 "document.title"

node scripts/cdp.mjs eval A1B2 "window.location.href"

node scripts/cdp.mjs eval A1B2 "document.querySelectorAll('a').length"

Navigate to URL

node scripts/cdp.mjs nav A1B2 https://example.com

# Navigates and waits for page load

Network Resource Timing

node scripts/cdp.mjs net A1B2

# Shows network resource timing for the current page

Click an Element

node scripts/cdp.mjs click A1B2 "button.submit"

node scripts/cdp.mjs click A1B2 "#login-btn"

node scripts/cdp.mjs click A1B2 "[data-testid='confirm']"

Click at Coordinates

node scripts/cdp.mjs clickxy A1B2 320 480

# Clicks at CSS pixel coordinates (x=320, y=480)

Type Text

node scripts/cdp.mjs type A1B2 "Hello, world!"

# Types at the currently focused element — works in cross-origin iframes

Load More (Click Until Gone)

node scripts/cdp.mjs loadall A1B2 "button.load-more"

# Keeps clicking the selector until it disappears from the DOM

Open a New Tab

node scripts/cdp.mjs open

node scripts/cdp.mjs open https://example.com

# Note: triggers Chrome's "Allow" prompt

Stop Daemons

node scripts/cdp.mjs stop          # stop all daemons

node scripts/cdp.mjs stop A1B2     # stop daemon for specific tab

Raw CDP Command Passthrough

node scripts/cdp.mjs evalraw A1B2 "Page.getFrameTree"

node scripts/cdp.mjs evalraw A1B2 "Runtime.evaluate" '{"expression":"1+1"}'

Common Patterns

Pattern: Read a Page You're Logged Into

# List tabs to find your target

node scripts/cdp.mjs list

# Grab the accessibility tree for a semantic view

node scripts/cdp.mjs snap D4E5

# Or get scoped HTML for a specific section

node scripts/cdp.mjs html D4E5 ".email-list"

Pattern: Fill and Submit a Form

# Click the input field

node scripts/cdp.mjs click A1B2 "input[name='search']"

# Type into it

node scripts/cdp.mjs type A1B2 "my search query"

# Click submit

node scripts/cdp.mjs click A1B2 "button[type='submit']"

# Take a screenshot to verify result

node scripts/cdp.mjs shot A1B2

Pattern: Extract Data with JavaScript

# Get all link hrefs on a page

node scripts/cdp.mjs eval A1B2 "Array.from(document.querySelectorAll('a')).map(a => a.href)"

# Get text content of a specific element

node scripts/cdp.mjs eval A1B2 "document.querySelector('.price').textContent.trim()"

# Get table data as JSON

node scripts/cdp.mjs eval A1B2 "

  Array.from(document.querySelectorAll('table tr')).map(row =>

    Array.from(row.querySelectorAll('td,th')).map(cell => cell.textContent.trim())

  )

"

Pattern: Navigate and Wait

# Navigate and then immediately read the page

node scripts/cdp.mjs nav A1B2 https://news.ycombinator.com

node scripts/cdp.mjs snap A1B2

Pattern: Paginated Content

# Keep loading content until "Load More" button disappears

node scripts/cdp.mjs loadall A1B2 "button[data-action='load-more']"

# Then extract all loaded content

node scripts/cdp.mjs eval A1B2 "document.querySelectorAll('.item').length"

Pattern: Script Integration (Node.js)

import { execFile } from 'node:child_process';

import { promisify } from 'node:util';

const exec = promisify(execFile);

const CDP = (...args) => exec('node', ['scripts/cdp.mjs', ...args]);

async function getPageTitle(tabPrefix) {

  const { stdout } = await CDP('eval', tabPrefix, 'document.title');

  return stdout.trim();

}

async function takeScreenshot(tabPrefix) {

  const { stdout } = await CDP('shot', tabPrefix);

  return stdout.trim(); // returns file path

}

async function navigateAndSnap(tabPrefix, url) {

  await CDP('nav', tabPrefix, url);

  const { stdout } = await CDP('snap', tabPrefix);

  return stdout;

}

// Usage

const tabs = (await CDP('list')).stdout;

console.log(tabs);

Configuration

Environment Variable

Purpose

CDP_PORT_FILE

Path to DevToolsActivePort file for non-standard browser installs

Daemons auto-exit after 20 minutes of inactivity — no manual cleanup needed in normal use.

Troubleshooting

"Allow debugging" modal keeps appearing

This happens if daemons aren't persisting. Make sure you're using the same scripts/cdp.mjs entry point — it manages daemon lifecycle automatically. If you switched tools mid-session, run stop and let daemons restart fresh.

Browser not detected

If auto-detection fails, find your DevToolsActivePort file and set the env var:

# macOS Chrome example

export CDP_PORT_FILE="$HOME/Library/Application Support/Google/Chrome/Default/DevToolsActivePort"

# Linux Chrome example

export CDP_PORT_FILE="$HOME/.config/google-chrome/Default/DevToolsActivePort"

Target not found / prefix ambiguous

Run list again — tab IDs change when tabs are closed/reopened. Use a longer prefix if multiple tabs share the same prefix characters.

Remote debugging toggle not visible

Ensure you're on chrome://inspect/#remote-debugging (not just chrome://inspect/). The toggle is in the top-right of the page.

Node.js version error

This project requires Node.js 22+. Check with node --version and upgrade if needed via nvm or your package manager.

Screenshots are blank or wrong size

The screenshot reflects the actual rendered viewport. If the tab is in a background window or the OS has display scaling, pixel coordinates for clickxy may need adjustment. Use snap or eval to inspect DOM state instead of relying solely on screenshots.

Architecture Notes

• No Puppeteer, no Playwright, no intermediary — pure CDP WebSocket

• One persistent daemon process per tab (auto-spawned on first access)

• Daemon reuse is why 100+ tabs work reliably (no timeout on target enumeration)

• type uses CDP Input domain directly, bypassing iframe origin restrictions