Test Driven Development

This is TDD enforcement as a system prompt. It locks Claude into red-green-refactor with zero tolerance for shortcuts. Write a failing test first, watch it fail for the right reason, then write minimal code to pass it. The real teeth are in the rules: if you write implementation before tests, you delete it and start over, no exceptions. It catches the usual escape hatches like "I'll add tests after" or "I already manually tested it" and explains why they break the discipline. Includes a verification checklist, common excuses with rebuttals, and integration with anti-pattern docs. Useful if you want Claude to be strict about process, not just suggest best practices.