Conciseness

The body is mostly imperative and efficient — steps like 'strip internal headers from incoming requests, add correlation IDs, rewrite URL paths' pack concrete detail without explaining concepts Claude already knows. Not 5 because the Overview sentence ('unified entry point routing... centralized cross-cutting concern management') is wordier than needed and partly duplicates the description; not 3 because padding is minor, not 'several unnecessary explanations'.

Actionability

As an instruction-only skill, guidance is concrete: specific routing patterns ('/users/* -> user-service', 'X-API-Version: 2 -> v2-service'), specific headers ('X-User-ID', 'X-User-Roles'), exact output file paths, and an error table with concrete remedies ('Return Retry-After header; serve cached response'). Not 5 because no code, commands, or sample config snippets appear in SKILL.md itself; not 3 because the guidance includes specific, executable-level detail rather than high-level hints.

Workflow Clarity

The 9 instructions form a clear, logical sequence (inventory -> routing -> auth -> rate limiting -> transformation -> aggregation -> circuit breaker -> health -> tests) ending with an explicit verification step ('Write integration tests covering routing correctness, auth enforcement, rate limiting, circuit breaker behavior'). Not 5 because validation appears only at the end with no mid-workflow checkpoints or feedback loops; not 3 because the sequence is well-defined and testing plus the error-handling table supply most checkpoints.

Progressive Disclosure

The body is a concise overview with three clearly signaled, purpose-labeled references ('See references/implementation.md for the full implementation guide', 'Refer to references/errors.md for comprehensive error patterns', 'See references/examples.md for additional examples'), all of which exist and go only one level deep with no nested references. This matches the anchor for a clear overview with well-signaled one-level-deep references and easy navigation.

Specificity

The description lists several concrete actions — 'routing, load balancing, rate limiting, and authentication' — but omits other capabilities the skill actually covers (request transformation, response aggregation), matching 'several specific actions; minor gaps in coverage'. Not 5 because coverage is incomplete; not 3 because it names more than 1-2 actions in a specific domain.

Completeness

It explicitly answers what ('Create API gateways with routing, load balancing, rate limiting, and authentication') and when ('Use when routing and managing multiple API services') plus concrete trigger phrases, exactly matching the anchor for clearly answering both with concrete triggers.

Trigger Term Quality

Natural trigger phrases like 'build API gateway', 'create API router', and 'setup API gateway' plus 'routing and managing multiple API services' give good keyword coverage. Not 5 because common synonyms such as 'API proxy', 'reverse proxy', 'BFF', or specific framework names are missing; not 3 because the terms present are natural phrases users would say, not jargon.

Distinctiveness Conflict Risk

'API gateway' is a clear niche with distinct, gateway-specific trigger phrases, so conflict risk with other skills is minimal. Anchor 4 would require notable overlap with closely related skills (e.g., reverse-proxy or general API-development skills), which the trigger phrasing avoids.