The body is lean and assumes domain competence — it documents project-specific conventions (workspace reuse, env vars, judge model) rather than explaining concepts Claude already knows, and the Good/Bad example lists earn their tokens as actionable heuristics; it avoids the 'explains concepts Claude knows' pitfall of level 1 and the 'could be tightened' weakness of level 2.

It provides copy-paste-ready executable commands ('bun install', 'bun run cli -- run global ...', the env-var invocation) plus concrete numbered authoring rules and worked Good/Bad examples, matching the 'fully executable, copy-paste ready' anchor rather than the pseudocode/incomplete level-2 anchor.

Steps are clearly sequenced (running benchmarks with env setup, a numbered authoring-rules list, and an explicit validation checklist distinguishing hard checks from semantic expectations); the operation is non-destructive (upserting an eval resource), so the absence of a destructive feedback loop does not cap the score, fitting the clear-sequence-with-checklist anchor.

The body is well-organized into clearly delineated sections with a single, well-signaled one-level reference ('See ai_evals/README.md for the full case format'); no bundle files exist to nest, so the structure avoids the multi-level-reference and monolithic-wall pitfalls of the lower anchors.

Lists multiple concrete actions — 'Author and run black-box benchmark cases', 'adding or changing eval cases', and 'running before/after benchmarks' — matching the 'lists multiple specific concrete actions' anchor; it is not the level-2 anchor because it goes beyond naming a domain to enumerating several distinct actions.

It states what the skill does (author/run black-box benchmark cases) and provides an explicit 'Use when...' clause for when to invoke it, satisfying both halves; the level-2 anchor is excluded because the 'when' is explicit rather than implied.

Natural trigger phrases users would say are present ('adding or changing eval cases', 'running before/after benchmarks for AI chat / copilot changes'); the embedded mode list (flow/app/script/cli/global) is project jargon but the surrounding triggers are natural, so it fits the good-coverage anchor rather than the 'some keywords, missing variations' level below.

The niche is sharply scoped to Windmill AI generation evals in ai_evals/ with distinct triggers, making it unlikely to fire for an unrelated skill; it is well above the 'somewhat specific but could overlap' level-2 anchor.