Conciseness

The ~20-line body wastes nothing: a one-line scope statement ('MapKit for SwiftUI — maps, annotations, and location features (iOS 26+)'), a lean file table, and three terse fetch steps. Every token earns its place and nothing explains concepts Claude already knows, matching the 'lean and efficient' anchor.

Actionability

Guidance is concrete and executable: the table maps each topic to an exact file (e.g., 'marker.md | Marker (pin-style annotations)'), and step 3 gives a copy-paste-ready URL rule ('/documentation/mapkit/mkmapview' maps to 'https://sosumi.ai/documentation/mapkit/mkmapview') for the one non-obvious operation. As an instruction-only skill, the absence of code is not penalized.

Workflow Clarity

The doc-lookup fallback is an unambiguous if/else chain ('Search this skill's local .md files first' → 'If the topic is not here' → 'If no installed skill has the page'), with the source for documentation paths named ('mapkit-overview.md'). This is a simple single-purpose lookup skill with no destructive or batch operations, so the simple-skill exception applies and the single action is unambiguous.

Progressive Disclosure

The body is a pure index: seven flat, one-level-deep .md files, each with a one-line content description in a table ('mapkit-overview.md | Full MapKit framework index'), keeping SKILL.md as a lean overview with easy navigation — exactly the 'clear overview with well-signaled one-level-deep references' anchor.

Specificity

Names the domain ('API reference: MapKit for SwiftUI') and enumerates five concrete topics ('Map view, Marker, Annotation, camera positions, map features') — several specific items with minor gaps (e.g., user location, Look Around absent). It sits at anchor 4, not 5 (coverage is not comprehensive) and not 3 (more than 1-2 concrete items are listed).

Completeness

The 'what' is explicit ('API reference: MapKit for SwiftUI. Map view, Marker, Annotation, camera positions, map features.'), but there is no 'Use when...' clause or equivalent trigger guidance, which caps completeness at 3 per the judging guidelines. It is above 2 because 'what' is clear, and below 4 because 'when' is entirely absent rather than merely imprecise.

Trigger Term Quality

'MapKit', 'SwiftUI', 'Map', 'Marker', 'Annotation', and 'camera positions' are terms users naturally say when asking about SwiftUI maps. A few common synonyms ('pins', 'location', 'coordinates') are missing, matching anchor 4 ('good keyword coverage; a few natural terms missing') rather than the comprehensive synonym coverage of anchor 5.

Distinctiveness Conflict Risk

'MapKit for SwiftUI' carves a mostly distinct niche among Apple-framework reference skills, but terms like 'Annotation' and 'map features' carry minor overlap risk with closely related skills (e.g., a general SwiftUI or CoreLocation reference). This matches anchor 4 ('mostly distinct; minor overlap risk') rather than the clear-niche, minimal-conflict profile of anchor 5.