Lists multiple specific concrete actions: defining API schemas, database schemas, REST/GraphQL endpoints, server-side validation, authentication, migrations, and backend logic. These are concrete, actionable capabilities.

Clearly answers both 'what' (defining APIs, database schemas, server logic, authentication, migrations) and 'when' with an explicit 'Use quando' clause and a detailed 'Trigger em' list providing specific activation keywords.

Excellent coverage of natural trigger terms including both general terms ('API', 'endpoint', 'banco de dados', 'backend', 'servidor') and specific technologies ('JWT', 'Prisma', 'PostgreSQL', 'Node.js', 'Express', 'NestJS', 'ORM'). These are terms users would naturally use when requesting backend work.

Clearly scoped to backend development with distinct triggers like 'migration', 'ORM', 'Prisma', 'middleware', 'JWT', and 'server-side validation' that are unlikely to conflict with frontend, DevOps, or other skill domains.

The skill is extremely verbose at ~350+ lines, inlining extensive code examples for schemas, middleware, services, validators, and an entire alternative stack (better-sqlite3) that could easily be in referenced files. It explains many patterns Claude already knows (base CRUD services, JWT auth flows, Zod validation) in full detail rather than providing only project-specific conventions.

The skill provides fully executable, copy-paste-ready code examples throughout — Prisma schemas, Zod validators, Express middleware, service patterns, SQLite repositories, and migration scripts. Endpoint patterns, response formats, and auth flows are all concrete and specific.

The auth flow and migration strategy have clear sequential steps, and the zero-downtime migration checklist is well-structured with a rollback step. However, there are no explicit validation checkpoints for the main development workflow (e.g., 'run tests after creating endpoints', 'validate schema before migrating'), and the overall process of going from inputs to outputs lacks a sequenced workflow with feedback loops.

The skill references `docs/skill-guides/backend-api.md` for extended examples but then proceeds to inline massive amounts of code that should be in that referenced file. The entire alternative stack section (better-sqlite3), full middleware implementations, and service patterns are all inlined, creating a monolithic document. References to governance policies are listed but the content itself doesn't leverage progressive disclosure effectively.