Conciseness

The ~68-line body contains only v9-specific, non-inferable knowledge (registration ordering, feature-slot vs table-option distinction, prerequisite pairs, stockFeatures tradeoff) with zero filler and no explanation of general table or React concepts. Every sentence carries information Claude could not derive on its own, matching the 'every token earns its place' anchor; not 4 because no section is trimmable without losing real guidance.

Actionability

The registration snippet is complete and executable (real imports, `tableFeatures()` call, exported `features` object), and the rules cite exact identifiers (`sortFn_alphanumeric`, `columnResizingFeature` requires `columnSizingFeature`, `FeatureSlotPrereqs`) plus a concrete inspection path (`node_modules/@tanstack/table-core/dist/types/TableFeatures.d.ts`). Not 4: the single example covers the universal registration pattern that all feature cases share, and feature-specific code is properly delegated to per-feature references (verified substantive, e.g. references/sorting.md has runnable setup code).

Workflow Clarity

A coherent sequence is present — read core skill first, register features per the rules, select only task-relevant references, inspect installed dist types — with a debugging checkpoint ('A missing API can mean missing registration. Check the concrete feature object before casting...'). Not 5: the sequence is implied by section order rather than explicit numbered steps, and there is no validate-then-retry loop for the debug path; not 3 because the flow is unambiguous and a real error-recovery checkpoint exists.

Progressive Disclosure

The body is a lean overview that splits all feature detail into 18 one-level-deep reference files, each linked from a task-symptom navigation table ('Sorting, comparators, undefined values, or sort interaction cycles → references/sorting.md'), all of which exist and contain substantive content. Navigation is by explicit symptom-to-reference mapping; sibling skills (core, table-state) are clearly signaled. This matches the 'clear overview with well-signaled one-level-deep references' anchor.

Specificity

'Add or debug Table v9 features: registration, row-model slots, prerequisites, sorting, filtering, pagination, selection, spanning, and column layout' names two concrete actions and comprehensively enumerates the feature areas the skill's 18 references cover. Not 4: the only compression is lumping ordering/pinning/resizing/visibility/sizing under 'column layout', which is a minor grouping rather than a coverage gap.

Completeness

The 'what' is explicit and concrete (add/debug Table v9 features with an enumerated list), but there is no 'Use when...' clause or equivalent explicit trigger guidance; 'Read only task-relevant feature references' is an instruction, not a 'when'. Per the judging guideline, a missing 'Use when' clause caps completeness at 3; it is not 4 because 'when' is entirely absent rather than merely imprecise.

Trigger Term Quality

Natural terms users would say are present ('sorting', 'filtering', 'pagination', 'selection', 'debug', 'column layout', 'Table v9'), but common variations are missing: no 'grouping', 'expanding', 'faceting', or the library name 'TanStack Table'. Not 5 because anchor 5 requires synonyms/comprehensive variations; not 3 because coverage goes well beyond 'some relevant keywords'.

Distinctiveness Conflict Risk

'Table v9 features' carves a clear niche with feature-specific triggers (row-model slots, prerequisites, spanning), unlikely to fire for unrelated skills. Not 5: it sits in a sibling family with the referenced 'core' and 'table-state' table skills, so a query about general table setup could plausibly match multiple family members — minor overlap risk with closely related skills.