Conciseness

Every line is project-specific, non-derivable fact — exact commands, paths, hash files, error codes (E0639), and attribute forms — with zero padding or explanation of concepts Claude already knows. It matches 'lean and efficient; every token earns its place'; anchor 4 would require trimmable over-explanation, and none is evident.

Actionability

Guidance is fully executable throughout: "task alef:generate → alef all --clean", "alef verify --exit-code", "cargo check -p xberg-ffi", "cargo install --path . --force", the exact attribute "#[cfg_attr(alef, alef(skip))]" with placement guidance, and canonical task enumerations. This meets 'copy-paste ready commands covering the common cases' — anchor 5, not 4, since there are no gaps in the core workflow.

Workflow Clarity

The 6-step workflow is clearly sequenced with explicit validation checkpoints (alef:verify, e2e:generate then e2e:test) and an atomic-commit instruction, plus a diagnostic feedback loop ("Check this first when a regen dies") and a corrective path ("Fix alef.toml or the Rust source, then regenerate and re-verify"). The batch regen operation is validated, so the ≤3 cap for unvalidated batch operations does not apply.

Progressive Disclosure

The body is well-sectioned with clear headers (Workflow, Freshness check, alef.toml sections, breaking edits, FFI bridge), but ~85 dense lines are all inline with no bundle files — the alef.toml section enumeration and FFI-bridge marshalling detail would fit naturally in one-level-deep references/*. Not 5 because the <50-line simple-skill exception doesn't apply and no external references exist to signal; not 3 because structure and content placement are otherwise appropriate and navigable.

Specificity

The description enumerates four concrete capabilities with exact task names — "the regeneration workflow (task alef:generate / alef:verify)", "the alef.toml section layout", "the core-side edits that break a regen", and "the FFI bridge's JSON marshalling requirement" — with comprehensive coverage and no filler. It clearly matches the anchor-5 example rather than anchor 4, which requires minor coverage gaps that are absent here.

Completeness

Both 'what' (the four named topics) and 'when' ("Load before editing anything under packages/* or a binding crate, before adding a trait method or extractor, or when regenerating or verifying Alef output") are explicit and concrete, mirroring the anchor-5 example structure. Not 4, because the 'when' clause is fully explicit rather than improvable.

Trigger Term Quality

Natural phrases a user would actually say are covered: "editing anything under packages/* or a binding crate", "adding a trait method or extractor", "regenerating or verifying Alef output", plus concrete artifacts (packages/*, alef.toml, task names). This matches the comprehensive anchor including file-path/glob variants; nothing obvious is missing within this niche domain.

Distinctiveness Conflict Risk

A clear niche — Alef-managed generated bindings for a specific workspace — with distinct triggers (alef:*, alef.toml, binding crates) and minimal realistic conflict with other skills. Anchor 5 fits; there is no overlap risk with broader document- or code-skills.