Browser testing with DevTools
Uses the DevTools protocol to inspect, measure and reproduce behaviour in a live page.
Installation
$ npx skills add addyosmani/agent-skillsThe CLI's unit is the repository, so this installs everything in addyosmani/agent-skills, not browser-testing-with-devtools alone. It writes into whichever agent directories it finds — Claude Code, Codex, Cursor, Copilot, Windsurf, Zed.
Summary
Uses the DevTools protocol to inspect, measure and reproduce behaviour in a live page.
- Reach for it when a bug that only exists in the browser, and only with the real network and real data.
- Spans Test and Operate & maintain, so it is usually worth loading for the whole piece of work rather than at one moment in it.
- Assumes web.
- Published by Addy Osmani. Well regarded, but not the vendor of the thing it covers.
- Installing pulls the whole addyosmani/agent-skills repository: this catalogue lists 19 other entries from it, and the repo may hold more.
Where it sits in delivery
TestProving the change does what it claims — and finding the assertions that were never written.Everything in Test →
Operate & maintainProduction reality: debugging, performance, instrumentation, and writing down why the system is the way it is.Everything in Operate →
The agent itself
The full text lives with its publisher and changes when they change it. Read it there rather than here — a mirrored copy of somebody else's procedure goes stale silently, and this page would have no way of telling you.
Related
More in Test
- Code testing agentA multi-agent pipeline that researches, plans and then generates a working test suite — language-agnostic despite the publisher.
dotnet/skills - Test gap analysisFinds the behaviour that no test currently exercises and reports it as a list.
dotnet/skills - Webapp testingDrives a real browser against a running app and reports what it found.
anthropics/skills - DiagnoseA diagnosis loop that ends in a regression test, not just a green build.
mattpocock/skills - GitHub triageTriages issues and pull requests into something a maintainer can work through.
trailofbits/skills - Analyzing .NET performanceTraces, dumps and allocation analysis, from the team that builds the runtime.Skill
dotnet/skills