Decide which tests to write, keep, and delete, and prove a change works before calling it done. Test only business logic and its corner cases. Run the real thing on every target before reporting a fix. Delete tests for removed or replaced behavior.
Install
npx skills add skrrt-sh/skills --skill testingnpx skills add skrrt-sh/skills --skill testing -a claude-code -gnpx skills add skrrt-sh/skills --skill testing -a codex -ggemini skills install https://github.com/skrrt-sh/skills.git --path skills/dev/testinggh skill install skrrt-sh/skills testinggit clone --depth 1 https://github.com/skrrt-sh/skills /tmp/skrrt-sh__skills
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/skrrt-sh__skills/skills/dev/testing ~/.claude/skills/testing # Claude Code
cp -R /tmp/skrrt-sh__skills/skills/dev/testing ~/.agents/skills/testing # Codex, Cursor, Gemini CLI, Copilot, OpenCode