Conciseness

The body is largely efficient with clean code blocks and useful non-obvious specifics (Cloudflare Workers runtime, 30s timeout, no fs), but contains some trimmable prose and repeated patterns across HTTP-method examples. It is above 3 because most content earns its place, but not a 5 due to minor padding.

Actionability

Provides abundant copy-paste-ready, executable code and concrete commands (npx expo serve, eas deploy, eas env:create) covering the common cases from CRUD through CORS, env vars, databases, and auth. Fully actionable with no significant gaps.

Workflow Clarity

The deployment section gives a clear sequence (install eas-cli, login, deploy, set env, custom domain) and topics are well organized, with only minor validation gaps (no explicit 'verify the deployed endpoint' checkpoint). Not a 5 because explicit validation/feedback loops are absent, though the operations are non-destructive so no cap at 3 applies.

Progressive Disclosure

A single self-contained file with clear, logical section headers and no nested or broken references; no bundle files are provided so all content is appropriately inline. Not a 5 because some advanced material (runtime constraints, common patterns) could be split into reference files, but structure is good with only minor organization gaps.

Specificity

Names the domain concretely ('API routes in Expo Router with EAS Hosting') and one concrete action ('creating'), but offers only a single action rather than comprehensive coverage. It sits above score 2's generic 'names the domain' but lacks the multiple specific actions needed for a 4.

Completeness

It clearly states what the skill covers ('Guidelines for creating API routes...') but provides no 'Use when...' clause or equivalent explicit trigger guidance, which per the rubric caps completeness at 3. It is not a 4 because the 'when' is entirely absent rather than merely weak.

Trigger Term Quality

Includes natural terms an Expo developer would say ('API routes', 'Expo Router', 'EAS Hosting') with good coverage, but omits common synonyms like 'backend', 'server endpoints', or 'endpoints'. Not a 5 because those variations are missing, but clearly above the sparse keyword level of 3.

Distinctiveness Conflict Risk

The Expo Router + EAS Hosting niche is specific and unlikely to trigger the wrong skill, with only minor overlap risk against general backend/API skills. Not a 5 because there are no explicit distinct trigger phrases to fully separate it from adjacent backend skills.