Vendored from anthropics/skills under Apache-2.0. Modified: description rewrite, a Delegating section pointing at the paired webapp-tester agent shipped in this repo, a tone pass (emoji and all-caps emphasis removed), a wait-discipline pass replacing the fixed-duration wait_for_timeout advice and its two example uses with condition waits, and a Limits note that a screenshot gets read and judged, with a pixel diff as the secondary check.

Web Application Testing

To test local web applications, write native Python Playwright scripts.

Helper Scripts Available:

• scripts/with_server.py - Manages server lifecycle (supports multiple servers)

Always run scripts with --help first to see usage. Don't read the source until the script has been run and shown not to fit the task. These scripts can be large; reading them pollutes your context window. They exist to be called directly as black boxes.

Decision Tree: Choosing Your Approach

UI/frontend only. For pure backend/API assertions without a browser, use Playwright's request context or a plain HTTP client instead (see Limits).