chrome-cdp

name	chrome-cdp
description	Interact with local Chrome browser session (only on explicit user approval after being asked to inspect, debug, or interact with a page open in Chrome)

Chrome CDP

Lightweight Chrome DevTools Protocol CLI. Connects directly via WebSocket — no Puppeteer, works with 100+ tabs, instant connection.

Prerequisites

• Chrome (or Chromium, Brave, Edge, Vivaldi) with remote debugging enabled: open chrome://inspect/#remote-debugging and toggle the switch
• Node.js 22+ (uses built-in WebSocket)
• If your browser's DevToolsActivePort is in a non-standard location, set CDP_PORT_FILE to its full path
• For remote/cloud CDP, set CDP_URL to a direct ws:///wss:// browser endpoint. CHROME_CDP_URL and BROWSER_CDP_URL are accepted aliases. http:///https:// endpoints are also accepted when /json/version exposes webSocketDebuggerUrl.

Commands

All commands use scripts/cdp.mjs. The <target> is a unique targetId prefix from list; copy the full prefix shown in the list output (for example 6BE827FA). The CLI rejects ambiguous prefixes.

List open pages

scripts/cdp.mjs list

Take a screenshot

scripts/cdp.mjs shot <target> [file]    # default: screenshot-<target>.png in runtime dir

Captures the viewport only. Scroll first with eval if you need content below the fold. Output includes the page's DPR and coordinate conversion hint (see Coordinates below).

Accessibility tree snapshot

scripts/cdp.mjs snap <target>

Evaluate JavaScript

scripts/cdp.mjs eval <target> <expr>

Watch out: avoid index-based selection (querySelectorAll(...)[i]) across multiple eval calls when the DOM can change between them (e.g. after clicking Ignore, card indices shift). Collect all data in one eval or use stable selectors.

Other commands

scripts/cdp.mjs html    <target> [selector]   # full page or element HTML
scripts/cdp.mjs nav     <target> <url>         # navigate and wait for load
scripts/cdp.mjs net     <target>               # resource timing entries
scripts/cdp.mjs click   <target> <selector>    # click element by CSS selector
scripts/cdp.mjs clickxy <target> <x> <y>       # click at CSS pixel coords
scripts/cdp.mjs type    <target> <text>         # Input.insertText at current focus; works in cross-origin iframes unlike eval
scripts/cdp.mjs loadall <target> <selector> [ms]  # click "load more" until gone (default 1500ms between clicks)
scripts/cdp.mjs evalraw <target> <method> [json]  # raw CDP command passthrough
scripts/cdp.mjs open    [url]                  # open new tab (each triggers Allow prompt)
scripts/cdp.mjs stop    [target]               # stop daemon(s)

Coordinates

shot saves an image at native resolution: image pixels = CSS pixels × DPR. CDP Input events (clickxy etc.) take CSS pixels.

CSS px = screenshot image px / DPR

shot prints the DPR for the current page. Typical Retina (DPR=2): divide screenshot coords by 2.

Tips

• Prefer snap --compact over html for page structure.
• Use type (not eval) to enter text in cross-origin iframes — click/clickxy to focus first, then type.
• Chrome shows an "Allow debugging" modal once per tab on first access. A background daemon keeps the session alive so subsequent commands need no further approval. Daemons auto-exit after 20 minutes of inactivity.

Agent guidance — CDP connection

When a skill requires Chrome CDP and connection fails:

1. If CDP_URL is provided, use it first. This is the expected path for Browser Use Cloud or other remote persistent browser profiles. Example shape: CDP_URL='wss://connect.browser-use.com?apiKey=...&profileId=...' scripts/cdp.mjs list. Do not print secrets in logs.
2. Otherwise try the command first — scripts/cdp.mjs list will auto-discover Chrome via DevToolsActivePort
3. If connection fails — launch a dedicated Chrome instance yourself, passing the skill's target URL as an argument so Chrome opens directly on the login page. A fresh profile has no tabs, so skills that look for a specific site will fail without this. The binary name varies by system:
   • macOS: "/Applications/Google Chrome.app/Contents/MacOS/Google Chrome" --remote-debugging-port=9222 --user-data-dir=$HOME/Library/Application\ Support/showrun/chrome-profile --no-first-run "<target-url>" &
   • Linux: try google-chrome-stable, google-chrome, or chromium — whichever is available:

     google-chrome-stable --remote-debugging-port=9222 --user-data-dir=$HOME/.local/share/showrun/chrome-profile --no-first-run "<target-url>" &
     

   Replace <target-url> with the skill's login page (e.g. https://my.pitchbook.com for PitchBook, https://www.crunchbase.com for Crunchbase, https://www.linkedin.com for LinkedIn). Wait a few seconds, then retry. This profile persists across sessions — users only need to log in once.
4. If Chrome is already running via CDP but the target site isn't open, open it via scripts/cdp.mjs open <target-url> instead of asking the user.
5. If the user is not logged in to the required platform — ask them to log in in the Chrome window you just opened, then retry.