What problem does it solve? Teams building frontend and backend in parallel often suffer from silent contract drift, where API shapes diverge between sides and cause expensive integration failures. This Skill defines a single shared contract surface so every track codes against the same agreed shapes. ## Core Features & Use Cases - Contract Authoring: Creates one contract file per resource domain in board/contracts/ with request/response shapes, error shapes, shared types, and event payloads. - Schema Mirroring: Keeps zod or pydantic models derived from the contract file so the compiler catches drift instead of humans. - Change Ritual: Enforces a mandatory four-step process (edit contract, bump version, log in DECISIONS.md, notify consumers) before any code changes. - Use Case: When a backend developer needs to add a field to the scoring endpoint, they update the contract file, bump its version, record the decision, and notify consumers before touching implementation code. ## Quick Start Ask the AI to draft an API contract for a new resource domain following the template in .agents/templates/api-contract.md and place it in board/contracts/.
