Playwriter
A Chrome extension plus CLI that lets AI agents directly control the real Chrome browser you're using, reusing existing login sessions, extensions, and cookies, with full Chrome DevTools Protocol access.
About Playwriter
Playwriter is a Chrome extension plus CLI (command-line tool) that lets AI agents control the real Chrome browser you are actually using. Agents can directly use the browser's existing login sessions, extensions, and cookies, with no need to launch a headless browser instance. It gains full Chrome DevTools Protocol (CDP) access through the chrome.debugger permission inside the Chrome extension, rather than via an external CDP connection, so the remote debugging permission dialog is never triggered. The CLI sends Playwright code to the browser through a local WebSocket relay (localhost:19988). By default no remote servers are involved and browser data never leaves your computer; remote control is an optional feature that only turns on after you confirm the disclosure for the selected tab. File writes inside the execution sandbox are restricted to the session working directory and temporary directories such as /tmp. The extension's WebSocket endpoint validates origins and only accepts connections from the Playwriter extension itself, so malicious websites cannot connect and take control of your browser; remote access requires token authentication.
Best for
Best use cases
Let AI agents automatically perform actions on logged-in websites, reusing existing login sessions and cookies
Automation and debugging tasks that require setting breakpoints in page scripts, stepping through code, and inspecting variables at runtime
Live-editing page scripts and CSS without refreshing the page
Agent workflows that need to run unattended without repeatedly clicking Chrome permission dialogs
Compare before choosing
The official comparison page states: with Chrome's direct CDP connection, a permission dialog pops up on every connection, Chrome must be restarted, and startup depends on profile launch flags — whereas Playwriter never shows a permission dialog, can run unattended, and only requires clicking the extension icon once.
The official comparison page states: with Chrome's direct CDP connection, the login state depends on profile launch flags, while Playwriter directly uses the login state already present in the browser.
Features
Breakpoint Debugging
The official page states that it supports setting breakpoints, stepping through code, and inspecting variables at runtime, as well as live-editing page scripts and CSS without refreshing the page.
Full CDP Access
Provides full Chrome DevTools Protocol access, not a trimmed-down subset, so agents can invoke low-level debugging capabilities.
Uses Your Real Browser
The agent controls your real browser and can directly use existing login sessions, extensions, and cookies — no need to spin up a separate headless browser instance.
Origin Validation
The extension's WebSocket endpoint only accepts connections originating from the Playwriter extension, so malicious websites cannot forge the Origin and take control of your browser.
Sandboxed File System
Within the execution sandbox, write operations from require('node:fs') only succeed inside the session working directory and the system temporary directory.
Pros
- Agents can directly use existing login sessions, extensions, and cookies to operate the real browser — no headless instance needed
- Gains full CDP access through the extension's internals without triggering the remote debugging permission dialog, and can run unattended
- Everything is processed locally by default, so browser data never leaves your computer; remote control only turns on after explicit confirmation
- Supports breakpoint debugging, runtime variable inspection, and live editing of page scripts and CSS
- File writes are sandbox-restricted, and the extension endpoint performs origin validation