Conciseness

Quotes: "For optimization `EXP-*` targets, you are not selecting the winner or optimizing further..." (lines 11-13) followed by a second "For optimization `EXP-*` targets, act as an adversarial tester..." (lines 15-18), with the EXP-*/VAL-* semantics restated again in step 6 and after it (lines 96-110) — the target-type semantics are repeated roughly four times and could be consolidated. No basic-concept padding is present, so this fits anchor 3 ("Mostly efficient but includes some unnecessary explanation or could be tightened") better than anchor 2 (no heavily padded sections) or anchor 4 (the duplication is more than minor).

Actionability

Quotes: the concrete 7-step procedure with exact deliverables — "write `<regressions_dir>/<item_id>.md` with setup, command, expected credible measurement..." and "Call `end_node` with exactly one item for the assigned target id" — plus a copy-paste-ready markdown report template. This is an instruction-only skill whose concrete commands correctly live in the assigned contract, so absent code is not penalized; minor gaps (no worked example of an adversarial case or ledger entry) keep it at anchor 4 rather than anchor 5.

Workflow Clarity

Quotes: a clear 7-step sequence with explicit gating — "Required correctness/quality/compatibility/safety checks must run before objective metric comparison can promote a candidate", failure handling ("Failed checks make the candidate `rejected`, not promoted", "Missing, stale, skipped, or un-runnable checks make the experiment `invalid`"), and an outcome-classification checklist (promoted/rejected/budget_exhausted/invalid with decision rules). This matches anchor 5 ("Clear sequence with explicit validation steps; feedback loops for error recovery; checklists for complex processes"); anchor 4 falls short because validation checkpoints and failure-outcome handling are comprehensive rather than having minor gaps.

Progressive Disclosure

No bundle files exist (references/, scripts/, assets/ are all absent), so scoring is on structure alone: well-organized sections (Inputs, Procedure, Report) with the report template inlined where it is used. This is good structure with content appropriately placed for a self-contained operational procedure, matching anchor 4; it is not anchor 5 because the file exceeds the under-50-lines simple-skill exception and inline content like the ~30-line report template could arguably live in a reference file, nor anchor 3 since nothing is buried or clearly misplaced.

Specificity

Quotes: "independently classify candidate outcome", "prove or disprove the required benchmark/performance assertion" — the domain (benchmark validation) plus two concrete verdict-level actions are named, but coverage stops there; the actual validation activities (integrity audit, remeasurement, guardrail runs, reporting) are absent. This matches anchor 3 ("Names domain and 1-2 concrete actions, but not comprehensive") better than anchor 4, which expects several listed actions with only minor gaps.

Completeness

Quotes: "Benchmark validation procedure for one assigned benchmark-related target" gives a clear 'what', and "For optimization EXP-* targets... For engineering VAL-* or legacy engineering targets..." branch the behavior — but there is no 'Use when...' clause or equivalent explicit trigger guidance for when to invoke the skill, capping completeness at 3 per the judging guidelines. The 'when' is only weakly implied through the internal assignment framing.

Trigger Term Quality

Quotes: "Benchmark validation", "optimization EXP-* targets", "engineering VAL-*", "benchmark/performance assertion" — these are relevant domain keywords a user in this workflow could say, but there are no natural variations or synonyms (e.g., "validate an experiment", "performance regression", "benchmark check"), fitting anchor 3 ("Some relevant keywords but missing common variations or synonyms") rather than anchor 2 (terms are specific, not generic) or anchor 4 (coverage is not good yet).

Distinctiveness Conflict Risk

Quotes: "one assigned benchmark-related target", "EXP-*", "VAL-*" — the niche (independent validation of a single benchmark assertion, distinct from optimizing or selecting winners) is mostly distinct with distinctive target-type identifiers. It sits at anchor 4 rather than 5 because within a benchmark/optimization skill suite, sibling skills (experiment runners, optimizers) plausibly share the EXP-*/benchmark vocabulary, creating minor overlap risk.