Conciseness

The body is lean and role-organized with no explanation of concepts Claude already knows; every section is a few lines of high-value spec detail plus a focused code snippet. The lone version mention ('iOS 17.4+') is a durable deployment requirement rather than stale time-sensitive guidance, so it does not warrant the 4 anchor's 'over-explanation that could be trimmed'.

Actionability

Fully executable guidance throughout: real Info.plist keys, AppImpression with handleView/handleTap and the 15-minute window constraint, SKOverlay.AppConfiguration wiring, and Postback.updateConversionValue covering both fine/coarse values and lockPostback — copy-paste-ready snippets covering the common cases per role. Not 4, since there are no pseudocode or missing key details; undefined variables (signedJWS, adContainer) are inherent domain inputs explained in the surrounding text.

Workflow Clarity

Logical progression (publisher config → advertiser setup → impressions → conversion values) with explicit checkpoints — a Review Checklist and 'JWS signatures verified before counting conversions server-side' — but the steps are not explicitly sequenced and no error-recovery feedback loops are shown. Fits the 4 anchor ('clear sequence with most checkpoints present; minor validation gaps') rather than 5, which requires explicit sequencing with feedback loops, and rather than 3, since checkpoints are present.

Progressive Disclosure

SKILL.md is a clear overview with a navigable Contents TOC, and advanced material (postback verification, server handling, testing, SKAdNetwork migration) is split into a single, clearly signaled one-level-deep reference whose claimed contents match the actual references/adattributionkit-patterns.md file (verified: 582 lines, matching section headings, no nested .md references). Matches the 5 anchor.

Specificity

Lists multiple concrete actions — 'registering ad impressions, handling attribution postbacks, updating conversion values, implementing re-engagement attribution, configuring publisher or advertiser apps' — comprehensively covering the framework's surface, matching the 5 anchor rather than 4, which permits coverage gaps.

Completeness

Explicitly answers 'what' ('Measure ad effectiveness with privacy-preserving attribution using AdAttributionKit') and 'when' via an explicit 'Use when...' clause with six concrete trigger conditions, matching the 5 anchor; the 3-anchor cap for a missing 'Use when' clause does not apply.

Trigger Term Quality

Includes the natural phrases users of this domain would say: 'ad impressions', 'attribution postbacks', 'conversion values', 're-engagement attribution', 'replacing SKAdNetwork', 'publisher or advertiser apps', 'ad measurement'. Coverage is comprehensive for the domain, so it fits the 5 anchor rather than 4 ('a few natural terms missing').

Distinctiveness Conflict Risk

Occupies a clear niche (AdAttributionKit-based ad attribution, including explicit SKAdNetwork replacement triggers) with distinct, framework-specific trigger terms, so conflict risk with other skills is minimal.