What problem does it solve? Writing tests after the fact or testing implementation details produces brittle suites that break on refactors and verify nothing. This Skill enforces a disciplined red-green TDD loop so tests specify behavior through public interfaces and survive refactoring. ## Core Features & Use Cases - Red-Green Loop Discipline: Write the failing test first, watch it fail, then write only enough code to pass, one vertical slice per cycle. - Seam-Based Test Placement: Agree on testable seams (public interfaces) with the user before writing any test, so effort lands on critical paths. - Anti-Pattern Detection: Identifies implementation-coupled, tautological, horizontally sliced, and mock-testing tests, with a references/mocking.md guide covering mock completeness and complexity gates. - Use Case: When adding a checkout feature, confirm the public interface seams with the user, write one failing behavior test, implement the minimal code to pass, and repeat slice by slice. ## Quick Start Use the rc-tdd skill to build this feature test-first, starting by agreeing which seams we should test.
