Conciseness

The body is dense and information-rich with no beginner-concept padding (tables for key types, state types, and availability; terse code), but there is minor redundancy: "Register custom action types during setup before dispatching them" is restated as "Register each custom action type before dispatching it" two paragraphs later, and again in Common Mistakes and the checklist. This fits the 4 anchor (efficient, minor instances that could be trimmed) rather than 5, where every token would earn its place.

Actionability

Mostly executable, copy-paste-ready Swift covering the common cases (equipment conformances, built-in actions, delegate, renderer, GroupActivity manager), but a few snippets reference undefined symbols such as `seatPose0`, `counterID`, and the free `die`/`coinID` variables in the DieInteraction and custom-action examples. Fits the 4 anchor (concrete code with minor gaps); not 5 because those snippets are not fully self-contained, not 3 because the code is real and complete in structure rather than pseudocode.

Workflow Clarity

The main workflow is explicitly sequenced ("Build and validate a game in this order") with a validation feedback loop ("Inspect the current snapshot for required equipment IDs… Fix the setup and rebuild if an invariant fails"), the bookmark flow has explicit reconciliation checkpoints ("Wait for `stateDidResetToBookmark`, then read `withCurrentSnapshot`… validate the restored invariant"), and a Review Checklist closes the document. This matches the 5 anchor (clear sequence, explicit validation, feedback loops, checklist) rather than 4, where checkpoints would only be 'mostly' present.

Progressive Disclosure

The SKILL.md keeps overview-level guidance inline and consistently pushes extended patterns to a single, one-level-deep reference file with section-specific pointers ("for card fan, grid, and overlap layout examples", "Load [State Bookmarks and Undo](references/tabletopkit-patterns.md#state-bookmarks-and-undo)"); the referenced file exists, the anchor resolves to a real heading, and it contains no nested references. Matches the 5 anchor (clear overview, well-signaled one-level-deep references, easy navigation).

Specificity

Lists multiple concrete actions with comprehensive coverage: "Builds multiplayer spatial board games using TabletopKit on visionOS", "managing seats, turns, equipment state, TabletopAction flows, or TabletopInteraction delegates", "synchronizing gameplay through FaceTime Group Activities; rendering with RealityKit; or implementing snapping, tosses, and physics". Clearly matches the 5 anchor (multiple specific concrete actions, comprehensive coverage) rather than 4, since no capability area is left vague.

Completeness

Explicitly answers both questions: the "what" is "Builds multiplayer spatial board games using TabletopKit on visionOS" and the "when" is the concrete "Use when creating tabletop game experiences with boards, pieces, cards, or dice; managing seats, turns…" clause. This mirrors the 5 anchor's structure exactly, not the 4 anchor where the 'when' is less specific.

Trigger Term Quality

Comprehensive natural-term coverage including synonyms: "board games" / "tabletop game experiences", "pieces, cards, or dice", "seats, turns", "multiplayer", "FaceTime Group Activities", "RealityKit", "snapping, tosses, and physics". These are the phrases a visionOS developer would actually say, matching the 5 anchor; at most a minor synonym (SharePlay) is absent, which does not drop it to the 4 anchor's 'a few natural terms missing'.

Distinctiveness Conflict Risk

A clear niche with distinct triggers: TabletopKit, TabletopAction, TabletopInteraction, and visionOS-specific tabletop concepts leave virtually no overlap risk with other skills. Matches the 5 anchor; not 4, because the API names and trigger phrases are unique rather than merely 'mostly distinct'.