What problem does it solve? It coordinates the full TDD cycle for a single Go usecase (one command or one query) so the test is written and verified red before implementation turns it green, without mixing test and implementation conventions into one step. ## Core Features & Use Cases - Orchestrated TDD cycle: Runs fix-unit, write-failing-test, run-red, implement, run-green, refactor, align-errors, and report steps in declared order via playbook.yml. - Convention delegation: Delegates test shape to the usecase test convention, implementation form to the usecase implementation convention, language style to the Go coding convention, and error wrapping to the error convention without redefining them. - Stop and resume conditions: Classifies red-test failure reasons, halts on out-of-scope failures (missing Docker, red lower layers, missing rdbtest helpers), and resumes from the first incomplete step. - Use Case: Given a domain-rule document describing a business event like confirming a reservation, produce a usecase whose test exercises the five wiring concerns (input resolution, collaboration, source selection, transaction boundary, persistence) against a real database before the Execute method is implemented. ## Quick Start Implement this reservation-confirmation usecase with TDD, writing the failing test first and then making it green.