Conciseness

The body is mostly lean overview material, but 'When to use this skill' duplicates the frontmatter description nearly verbatim, and the Constraints section carries inherited boilerplate ('FUZZING: keep fuzzing guidance high-level...' generic rule, Maven compile/verify commands), Maven compile/verify commands) that is tangential to OpenAPI contract guidance — minor trimmable instances rather than severe padding.

Actionability

Step 1 gives a concrete pointer ('Read references/701-technologies-openapi.md and inspect current API/context artifacts') and the reference file genuinely contains executable YAML examples, but the body's own steps are generic direction — 'Execute appropriate checks', 'Implement or refactor artifacts following the reference patterns' — with no concrete commands or lint/validation specifics, matching 'some concrete guidance but incomplete'.

Workflow Clarity

The 4-step sequence (assess context, gather scope, apply changes, run verification and report) is clearly ordered and ends in a verification step, but the validation checkpoint is implicit and generic ('Execute appropriate checks') with no concrete validation command in the workflow — the same pattern as the anchor-3 example ending in 'Test the output', below anchor 4 which shows explicit commands per step.

Progressive Disclosure

The body is a genuine overview: scope summary, constraints, workflow, and a single well-signaled one-level-deep reference ('For detailed guidance, examples, and constraints, see references/701-technologies-openapi.md') that exists on disk and holds the 591 lines of concrete examples — clear split, easy navigation, no nesting.

Specificity

The description comprehensively enumerates capability areas ('spec structure, metadata and versioning, paths and operations, reusable schemas, security schemes, examples, documentation quality, contract validation (e.g. Spectral), breaking-change awareness, and handoffs to codegen') with named tools, but it lists topics rather than distinct concrete actions, so it sits at 'several specific actions; minor gaps' rather than fully action-based comprehensive coverage.

Completeness

It explicitly answers both 'what' (framework-agnostic OpenAPI 3.x guidance with a concrete capability list) and 'when' ('Use when you need framework-agnostic OpenAPI 3.x guidance... This should trigger for requests such as Review an OpenAPI...') with concrete trigger phrases, matching the top anchor; a 4 would require the 'when' to be weaker or less explicit than it is here.

Trigger Term Quality

Natural trigger phrases are explicit ('Review an OpenAPI; Improve an OpenAPI; Improve API contract; Improve API schema design') alongside terms like Spectral and codegen, but common synonyms users would say — 'Swagger', 'OpenAPI spec', 'API definition' — and file extensions (.yaml/.json) are missing, so keyword coverage is good but not comprehensive.

Distinctiveness Conflict Risk

The exclusion clause 'without choosing Spring Boot, Quarkus, or Micronaut' explicitly disambiguates this skill from framework-specific siblings, and 'Part of Plinth Toolkit' plus OpenAPI-specific triggers give it a clear niche with minimal overlap risk — it is not merely 'mostly distinct' (4) but fully distinct.