Best Testing skills for Claude Code

Looking for the best testing skills for Claude Code and other AI coding agents? This collection ranks 5 open-source testing skills by a blend of GitHub popularity, licensing clarity, and how well each one documents what it does. Skills — sometimes called Agent Skills — are small, shareable bundles of instructions that an agent loads on demand to become better at a specific job, so a strong testing skill can save you from re-explaining the same context in every session. The highest-ranked entries here, including Playwright Skill, Web Quality Skills, Claude Code Skills, pair an active repository with a real open-source license, which matters if you plan to adapt or redistribute them. Every listing links straight back to its original repository so you can read the source, check recent activity, and copy the exact install command. We refresh this ranking daily as stars, forks, and new releases change across the ecosystem.