What problem does it solve? When the same rule, threshold, ladder, or stated fact lives on two or more surfaces (web, iOS, Android, docs, a second service), hand-copied values silently drift apart, and users or answer engines discover the contradiction first. This Skill replaces manual copying with a generated contract so any divergence fails a test instead of reaching production. ## Core Features & Use Cases - Generated contracts: Builds a JSON contract by importing live constants from one designated reference surface, never by retyping values, with stable key ordering for byte-identical vendoring. - Staleness and follower tests: Adds a reference-side test that fails when the committed contract drifts from the code, plus follower tests that assert through public behavior rather than reimplementing formulas. - Divergence management: Records existing differences under knownDivergences with reasons, guards the exact expected set, and halts with a structured report when a new divergence is found mid-build. - Use Case: Your pricing threshold is defined in your web backend and copied into your iOS app. Use this Skill to generate a contract from the backend constants, vendor it byte-identical to the iOS repo, and add tests that fail the moment either side changes. ## Quick Start Use the suede-parity-contract skill to generate a parity contract from my reference service's constants and set up assertion tests in the follower app.
