Playwright Bowser

Purpose

Automate browsers using playwright-cli — a token-efficient CLI for Playwright. Runs headless by default, supports parallel sessions via named sessions (-s= ), and doesn't load tool schemas into context.

Key Details

• Headless by default — pass --headed to open to see the browser

• Parallel sessions — use -s=<name> to run multiple independent browser instances

• Persistent profiles — cookies and storage state preserved between calls

• Token-efficient — CLI-based, no accessibility trees or tool schemas in context

• Vision mode (opt-in) — set PLAYWRIGHT_MCP_CAPS=vision to receive screenshots as image responses in context instead of just saving to disk

Sessions

Always use a named session. Derive a short, descriptive kebab-case name from the user's prompt. This gives each task a persistent browser profile (cookies, localStorage, history) that accumulates across calls.

Derive session name from prompt context:

"test the checkout flow on mystore.com" → -s=mystore-checkout

"scrape pricing from competitor.com" → -s=competitor-pricing

"UI test the login page" → -s=login-ui-test

playwright-cli -s=mystore-checkout open https://mystore.com --persistent playwright-cli -s=mystore-checkout snapshot playwright-cli -s=mystore-checkout click e12

Managing sessions:

playwright-cli list # list all sessions playwright-cli close-all # close all sessions playwright-cli -s=<name> close # close specific session playwright-cli -s=<name> delete-data # wipe session profile

Quick Reference

Core: open [url], goto <url>, click <ref>, fill <ref> <text>, type <text>, snapshot, screenshot [ref], close Navigate: go-back, go-forward, reload Keyboard: press <key>, keydown <key>, keyup <key> Mouse: mousemove <x> <y>, mousedown, mouseup, mousewheel <dx> <dy> Tabs: tab-list, tab-new [url], tab-close [index], tab-select <index> Save: screenshot [ref], pdf, screenshot --filename=f Storage: state-save, state-load, cookie-, localstorage-, sessionstorage-* Network: route <pattern>, route-list, unroute, network DevTools: console, run-code <code>, tracing-start/stop, video-start/stop Sessions: -s=<name> <cmd>, list, close-all, kill-all Config: open --headed, open --browser=chrome, resize <w> <h>

Workflow

• Derive a session name from the user's prompt and open with --persistent to preserve cookies/state. Always set the viewport via env var at launch:

PLAYWRIGHT_MCP_VIEWPORT_SIZE=1440x900 playwright-cli -s=<session-name> open <url> --persistent

or headed:

PLAYWRIGHT_MCP_VIEWPORT_SIZE=1440x900 playwright-cli -s=<session-name> open <url> --persistent --headed

or with vision (screenshots returned as image responses in context):

PLAYWRIGHT_MCP_VIEWPORT_SIZE=1440x900 PLAYWRIGHT_MCP_CAPS=vision playwright-cli -s=<session-name> open <url> --persistent

• Get element references via snapshot:

playwright-cli snapshot

• Interact using refs from snapshot:

playwright-cli click <ref> playwright-cli fill <ref> "text" playwright-cli type "text" playwright-cli press Enter

• Capture results:

playwright-cli screenshot playwright-cli screenshot --filename=output.png

• Always close the session when done. This is not optional — close the named session after finishing your task:

playwright-cli -s=<session-name> close

Configuration

If a playwright-cli.json exists in the working directory, use it automatically. If the user provides a path to a config file, use --config path/to/config.json . Otherwise, skip configuration — the env var and CLI defaults are sufficient.

{ "browser": { "browserName": "chromium", "launchOptions": { "headless": true }, "contextOptions": { "viewport": { "width": 1440, "height": 900 } } }, "outputDir": "./screenshots" }

Full Help

Run playwright-cli --help or playwright-cli --help <command> for detailed command usage.

See docs/playwright-cli.md for full documentation.