Dense and assumes Claude's SQL/Drizzle competence; sections like 'The window' convey non-obvious deploy-cutover reasoning without padding about basics, so every token earns its place.

Provides executable commands (bunx drizzle-kit generate, bun run check:migrations, grep -rn "contract-pending") and concrete SQL/code blocks that are copy-paste ready.

Numbered Workflow with explicit validation (check:migrations), tiered error handling (hard errors / annotate tier / warnings), and a local 'Verify locally' step — destructive-op feedback loops are present, so it is not capped at 2.

No bundle files exist, so the skill is self-contained; its well-organized sections (window, expand/contract, playbook table, tracking, judgment, workflow, hard rule) provide clear navigation per the simple-skill allowance.

Lists multiple concrete actions — 'Author or review a Drizzle DB migration', 'expand/contract phasing', 'backward-compatibility with the deployed app version', and 'writing the -- migration-safe acknowledgment'.

Clearly states what the skill does (zero-downtime migration authoring/review) and gives an explicit 'Use when…' trigger clause.

The 'Use when adding/editing files under packages/db/migrations/ or changing packages/db/schema.ts' clause uses natural path and term triggers a user would actually name.

Scoped to Drizzle DB migrations with specific file paths, making it a clear niche unlikely to trigger for the wrong skill.