Conciseness

Every line carries non-inferable RevenueCat specifics (dashboard-configured UI, "Purchases.configure(…) must succeed", outermost-project rule, iOS-only refund requests, old-SDK fallback, exact callback names) with no generic-concept padding or over-explanation. This is the lean anchor-5 case: assumes Claude's competence and every token earns its place.

Actionability

Detection (exact file/dependency markers with an ordered first-match rule), the old-SDK fallback (logIn, customerInfo, restorePurchases, store URL), and verification are concretely executable, but the core implementation step says "Read the platform file" and promises an "install command, exact snippet to present the Customer Center, and the callback shape" — and none of the five referenced platforms/*.md files exist in the bundle. Key executable detail is missing, which is anchor 3, not 4; it is not 2 because most of the guidance outside section 3 is specific and executable.

Workflow Clarity

The sequence (detect platform → shared concepts → implement → verify) is clear and the verify section is a real checklist with explicit validation checkpoints (build succeeds, sandbox user with an active subscription, restore callback firing with a non-empty entitlements map, onDismiss) plus an error-recovery loop ("If the Customer Center opens but is empty ... Fix in the dashboard, reload, and retry"). This matches the anchor-5 feedback-loop pattern.

Progressive Disclosure

The in-body design is good — a clear overview with well-signaled, one-level-deep references — but scored against the actual bundle: only SKILL.md is present and all five referenced platforms/{ios,android,kmp,flutter,react-native}.md files are missing, so the disclosure structure points at nothing. Not 3, because the problem is not organization or signaling (both are good) but that every referenced detail file is absent; not 1, because the body itself is well structured rather than a monolithic or nested wall.

Specificity

The what-clause names the concrete artifact ("RevenueCat Customer Center (self service subscription management UI)") and the trigger clause enumerates specific actions and API names ("present CustomerCenterView", "call presentCustomerCenter", "wire a 'manage subscription' button"). This matches anchor 4 (several specific actions, minor gaps); it is not 5 because the capability side is a single integration action with features like dashboard configuration and lifecycle callbacks left implicit, and not 3 because multiple concrete actions are explicitly listed.

Completeness

Explicitly answers both: what ("Add the RevenueCat Customer Center (self service subscription management UI) to an app") and when, with a full "Use when the user asks to ..." clause containing concrete trigger phrases. This matches the anchor-5 example's structure exactly, so it is not the anchor-4 case where the when-clause is present but less explicit.

Trigger Term Quality

Covers natural phrasings ("add a customer center", "build a self service subscriptions screen", "let users manage subscriptions in app", "add a subscription management screen"), SDK-level triggers (CustomerCenterView, presentCustomerCenter), and all five platforms. A few natural terms users would say for this exact feature are missing ("cancel subscription", "request a refund", "restore purchases"), which fits anchor 4 rather than the comprehensive anchor 5.

Distinctiveness Conflict Risk

The niche is clear and RevenueCat/API-name triggers ("present CustomerCenterView", "call presentCustomerCenter") are unambiguous. Generic unqualified phrases like "let users manage subscriptions in app" or "build a self service subscriptions screen" could fire on a custom (non-RevenueCat) subscription-management request or a closely related RevenueCat skill, which is exactly anchor 4's "minor overlap risk" rather than anchor 5's minimal risk.