Conciseness

The body is dense reference prose with no padding and no explanations of things Claude already knows: every section delivers a named lever ("context pointer", "information hierarchy", "leading word", "no-op"), its failure mode, and its cure, assuming the model's competence throughout (e.g. "The test (does it change behaviour versus the default?) is model-relative"). It matches anchor 5 ('lean and efficient; assumes Claude's competence; every token earns its place') rather than 4, because there is no over-explanatory passage that could simply be trimmed — even the illustrative asides ("_Don't think of an elephant_...") are single-sentence and carry the point they illustrate.

Actionability

For an instruction-only skill the guidance is concrete and testable throughout: explicit tests ("the document should read like documentation written for the agent"; the branch test "inline what every branch needs, and push behind a pointer what only some branches reach"; the no-op test "does it change behaviour versus the default?"), ordered procedures ("Defend in order: sharpen the bound first (local and cheap); only if it is irreducibly fuzzy... hide the later steps"), and worked rewrite examples ("'fast, deterministic, low-overhead' → _tight_", with the positive-phrasing alternative "write one-line comments"). This matches anchor 5's 'specific examples cover the common cases'; it is not 4 because there is no gap where guidance stays high-level without a concrete test or example.

Workflow Clarity

The skill is all-reference by design ("all reference (a review's rules, this skill)"), so there is no multi-step workflow to sequence, and no destructive or batch operations that would require validation checkpoints or impose a cap. The one procedural path present is explicitly ordered (sharpen the bound first, then split only if the rush is observed; sharpen the pointer wording first, inline only if sharpening fails), matching anchor 4's 'clear sequence with most checkpoints present' territory rather than 5, because the reference provides no overarching decision procedure ordering its many levers for a run (which lever to check first when auditing a document), and no verification checkpoint for the writer (e.g. a final pass or self-check).

Progressive Disclosure

Structure is good: eight well-scoped headings, and skill-specific mechanics are appropriately split out behind a clearly signaled, one-level-deep pointer ("When the document you're writing is a skill, read [SKILL-MECHANICS.md](SKILL-MECHANICS.md) for frontmatter, invocation choice, and router skills"), keeping the body general. This sits at anchor 4 rather than 5 because the referenced SKILL-MECHANICS.md could not be verified in the provided bundle (no references/, scripts/, or assets/ directories and no SKILL-MECHANICS.md file exist alongside SKILL.md), so the split's other side cannot be confirmed — a minor organization gap rather than the fully verified, well-signaled split of the 5-anchor.

Specificity

"Writing documents for agents" names the domain and the core action, and the when-clause names concrete artifacts ("creating or editing skills, or modifying AGENTS.md or CLAUDE.md"), but the what-clause lists no concrete capabilities of the reference itself (progressive disclosure, pruning, leading words are all absent). It matches the anchor 'Names domain and 1-2 concrete actions, but not comprehensive' rather than 2, because the named artifacts go beyond a bare verb-plus-object like 'Processes PDF files'; it is not 4 because no several specific actions are listed.

Completeness

Both parts are present: what ("Writing documents for agents") and an explicit when with concrete triggers ("Use when creating or editing skills, or modifying AGENTS.md or CLAUDE.md"). It sits between anchors 4 and 5 — the when-clause is fully explicit, but the what is terse and does not convey what the reference actually provides (structuring documents so agents consume them predictably), so the 'what' could be more informative as the 4-anchor describes.

Trigger Term Quality

Natural terms users would say are present — "skills", "creating", "editing", "AGENTS.md", "CLAUDE.md", "modifying" — which are strong, file-name-level triggers. It falls short of anchor 5 because common variations are missing: "instructions", "agent docs", "prompts", "documentation", "memory" files, or equivalents of the '.pdf'-style extension coverage.

Distinctiveness Conflict Risk

Naming AGENTS.md and CLAUDE.md explicitly gives clear, distinct triggers with minimal conflict risk against unrelated skills. Minor overlap remains with closely related skills (general documentation-writing or CLAUDE.md-generation skills like an init skill), matching anchor 4 rather than 5's 'clear niche with no overlap'.