7 agent skills for testing and debugging, each from its publisher's own repository or a large open-source project. Open a skill for its license, install command and the date we checked it.
mutation-testing is Trail of Bits' agent skill for configuring mutation testing campaigns with its mewt or muton tools, reading surviving mutants, telling equivalent mutants from real test gaps, and hunting bugs they expose.
playwright-cli is Microsoft's agent skill for driving a real browser from the terminal: open pages, click and fill by element reference, take snapshots and screenshots, mock requests and generate Playwright tests.
Systematic Debugging is an agent skill from Superpowers that makes your agent find the root cause of a bug or failing test before it proposes any fix, instead of guessing.
tdd is Matt Pocock's agent skill for test-driven development: the agent agrees which public interfaces to test with you, then works one failing test and one minimal fix at a time.
Test-Driven Development is an agent skill from Superpowers: your agent writes a failing test first, watches it fail, then writes only the code needed to make it pass.
Verification Before Completion is an agent skill from Superpowers: your agent runs the command that proves a claim and reads the output before it says work is done, fixed or passing.
Webapp Testing is Anthropic's open-source agent skill for testing local web apps: the agent writes Python Playwright scripts that click through your app, take screenshots and read console logs.