Ctrl C V Tdd

Test-pattern doctrine. Tests are copyable from ~/.claude/patterns/tests/, three categories: input boundary, contract, effect. Make sure to consult this skill whenever code changes touch a boundary where someone else's code meets yours, even if the user doesn't say "test" or "TDD" — Claude tends to ship untested boundary code, and this skill prevents the Saturday phone call. TRIGGER when: code under change has external callers (other modules, cron, CLI, HTTP/RPC clients, "外部调用", "被外部调用"); persists state (DB write, file write, redis/cache, session storage, anything that survives the request); calls third-party API/SDK; task is classified as LARGE per ctrl-c-v sizing (4+ files, new capability, new architecture, new external contract) — LARGE always triggers TDD regardless of caller scope; user mentions tests, TDD, 测试, boundary, contract, mock, fixture, red/green; business domain involves payments, queues, webhooks, auth, external integration. SKIP when: code change is purely internal helpers used only by caller in same file; pure UI rendering with no validation/state; accessor < 10 lines with no if/loop/exception; one-file fix that ctrl-c-v classifies as SMALL. Examples that trigger: "implement Stripe webhook handler", "add retry to the upload pipeline", "this database migration", "build a multi-step checkout form with validation across steps". Examples that skip: "rename this private function", "fix formatting in style.css".

mkdir -p ~/.claude/skills/ctrl-c-v-tdd
curl -L https://claudskills.com/skills/ctrl-c-v-tdd/SKILL.md \
  -o ~/.claude/skills/ctrl-c-v-tdd/SKILL.md

@misc{ctrl-c-v-tdd-2026,
  author    = {ClaudSkills},
  title     = {Ctrl C V Tdd [Claude Code skill]},
  year      = {2026},
  publisher = {ClaudSkills},
  url       = {https://claudskills.com/skills/ctrl-c-v-tdd/}
}