What problem does it solve? Codebases decay through accumulated small decisions — blurred module boundaries, duplicated logic, untyped contracts, tests that pin implementation instead of behavior — until a senior engineer needs weeks instead of hours to understand the code. This Skill provides a stack-agnostic field guide of code-health principles to consult while designing new modules and to score existing code against, catching structural decay before it compounds. ## Core Features & Use Cases - Design priming: Consult the principles while designing a new module, planning a refactor, or writing a spec that introduces new boundaries, so structure comes out right the first time. - Codebase scoring: Score an inherited or vibe-coded codebase Strong / Weak / Missing per principle with file:line evidence, then fix the one or two worst failures and re-score. - Eight principle families: Module boundaries, contracts, data discipline, behavior-pinning tests, errors/logs/audit, reasoning aids, operational properties, and economy — each with smells, moves, and explicit tradeoffs. - Use Case: When reviewing a large diff that introduces a new boundary, run this Skill alongside the per-diff review gate to audit whole-codebase structural properties a single-diff review skips. ## Quick Start Ask the assistant to score this codebase against the wf-codebase-health principles and report Strong, Weak, or Missing per principle with file:line evidence.
