Names the domain (RESTful API design) and lists several topic areas (HTTP semantics, caching, rate limiting), but describes itself as a 'quick reference' rather than listing specific concrete actions it performs.

Clearly answers both 'what' (quick reference for RESTful API design patterns, HTTP semantics, caching, rate limiting) and 'when' (explicit 'Triggers on:' clause with specific trigger terms), satisfying the requirement for explicit trigger guidance.

Excellent coverage of natural trigger terms users would say: 'rest api', 'http methods', 'status codes', 'api design', 'endpoint design', 'api versioning', 'rate limiting', 'caching headers' — these are all terms users would naturally use when seeking this kind of help.

The combination of REST API design patterns, HTTP semantics, caching, and rate limiting creates a clear niche. The specific trigger terms like 'status codes', 'endpoint design', and 'api versioning' make it unlikely to conflict with other skills.

The content is lean and well-structured using tables for maximum information density. It avoids explaining what REST is or how HTTP works—concepts Claude already knows—and focuses purely on quick-reference patterns.

The skill provides concrete patterns and examples (URL structures, query parameters, status codes) but lacks executable code examples for implementation. The caching headers and rate limiting mentioned in the description are not concretely demonstrated with actual header examples or implementation code.

This is a reference/lookup skill rather than a multi-step workflow, so the single-task clarity standard applies. The information is clearly organized into logical sections with unambiguous guidance, and the security checklist provides a clear validation checkpoint.

Excellent progressive disclosure: the main file serves as a concise overview with well-signaled one-level-deep references to four specific detail files (status-codes.md, caching-patterns.md, rate-limiting.md, response-formats.md) for deeper content.