Conciseness

The body is dense and instructional — lifecycle tables, key rules, and version-gated tracking guidance — with essentially no tutorial padding or explanation of what UIKit/SwiftUI are. Minor over-explanation could be trimmed: 'Why Coordinators Exist' re-explains that delegates require reference types (basic Swift knowledge), and 'Why updateUIView is the most important method' restates documented behavior. This fits anchor 4 ('efficient; minor instances of over-explanation') better than anchor 3, since the padding is a few sentences rather than whole padded sections.

Actionability

Most examples are complete, executable Swift (WrappedTextView, SearchBarView, DocumentScannerView + coordinator, the containment sequence, cell contentConfiguration). Two snippets are not runnable as written: the sizing-options fragment applies '@available(iOS 16.0, *)' to a bare property assignment, and the @MainActor coordinator example is a partial shell. This matches anchor 4 ('mostly executable guidance with minor gaps') rather than anchor 5's fully copy-paste-ready bar.

Workflow Clarity

Per-pattern sequences are explicit (make → update → dismantle timing table; addChild → constrain → didMove; delegate exits for success/cancel/error) and the 15-item Review Checklist acts as a validation checkpoint. It sits at anchor 4 ('clear sequence with most checkpoints present') rather than 5 because there is no single ordered start-to-finish flow for the most common task (e.g., choosing and adapting a wrapper recipe from the references) — the body teaches patterns rather than sequencing them. No destructive/batch operations exist, so the workflow-clarity cap does not apply.

Progressive Disclosure

SKILL.md is a well-navigable overview (TOC, sectioned patterns) that keeps core concepts inline and pushes bulk material to two real, one-level-deep reference files — references/representable-recipes.md (9 full wrapper recipes) and references/hosting-migration.md (migration patterns, including the 'Automatic Observation Tracking in UIKit' anchor the body links to, verified present). Both are signaled early with their purpose and again in the References section. This matches anchor 5 ('clear overview with well-signaled one-level-deep references; content appropriately split').

Specificity

The description names multiple concrete mechanisms — 'UIViewRepresentable, UIViewControllerRepresentable, UIHostingController, UIHostingConfiguration, coordinator delegates, and UIKit automatic observation tracking' — covering both bridge directions plus state sharing comprehensively. It matches the anchor 'Lists multiple specific concrete actions; comprehensive coverage' and exceeds anchor 4, which is reserved for coverage with minor gaps; no capability area of UIKit/SwiftUI interop is missing.

Completeness

It explicitly answers both questions: 'Bridges UIKit and SwiftUI with [named APIs]' states the what, and 'Use when wrapping… embedding… integrating… or migrating…' gives concrete trigger phrases. This matches anchor 5 ('clearly and explicitly answers both what AND when with concrete trigger phrases') and exceeds anchor 4, where the 'when' clause would be less specific.

Trigger Term Quality

Good natural keyword coverage: 'wrapping UIKit-only or third-party UIKit views/controllers in SwiftUI', 'embedding SwiftUI in UIKit', 'mail/share/document/PDF/text-view surfaces', 'migrating UIKit apps to SwiftUI incrementally'. A few natural terms users would actually say are missing (e.g., 'interop', 'hybrid app', 'share sheet', specific controller names like UIActivityViewController), so it fits anchor 4 ('good keyword coverage; a few natural terms missing') rather than the anchor-5 comprehensive-synonyms bar; it is clearly above anchor 3's 'some relevant keywords but missing common variations'.

Distinctiveness Conflict Risk

It occupies a clear niche (bidirectional UIKit/SwiftUI interop) with distinct triggers tied to specific APIs and integration surfaces, so it would not fire for generic SwiftUI or UIKit skills. This matches anchor 5; anchor 4 would apply only if there were notable overlap with a closely related skill, which there is not.