Explains how to develop Playwright - add APIs, MCP tools, CLI commands, and vendor dependencies.

Playwright Development Guide See [CLAUDE.md](../../../CLAUDE.md) for monorepo structure, build/test/lint commands, and coding conventions. Detailed Guides [Library Architecture](library.md) — client/server/dispatcher structure, protocol layer, DEPS rules [Adding and Modifying APIs](api.md) — define API docs, implement client/server, add tests [MCP Tools and CLI Commands](tools.md) — add MCP tools, CLI commands, config options [Vendor Dependencies & Bundling](vendor.md) — utilsBundle, coreBundle, babelBundle; adding vendored npm packages; DEPS.list; check deps [Updating WebKit Safari Version](webkit safari version.md) — update the Safari version string in the WebKit user agent [WebView (iOS Safari) Backend](webview.md) — webkit/webview/ against stock Mobile Safari; provisional target pause/resume; what's upstream vs Playwright patches; local + CI test setup [Bisecting Across Published Versions](bisect published versions.md) — reproduce regressions side by side from npm and diff node modules/playwright/lib/ between versions [Dashboard](dashboard.md) the UI powering the "playwright cli show" command, and how to work on it

playwright-dev