Conciseness

The body is dense and almost entirely non-obvious procedural content (no explanations of concepts Claude already knows), but there is noticeable redundancy: the atomic-commit and always-on-Verifier rules each appear in both 'Critical Rules' and 'Sub-Agent Delegation', the sub-agent offer is stated twice (Before Execute and the Sub-Agent trigger), and the script list appears in both the gates section and '.specs Structure'. This fits 'efficient; minor instances of over-explanation that could be trimmed' better than anchor 3, since nothing is wasted on background explanation.

Actionability

Concrete, copy-pasteable commands throughout: 'python3 <skill-dir>/scripts/validate_spec.py <spec-path-or-feature>', 'check_commit.py --message "<msg>"', plus exact artifact paths, an auto-sizing decision table, and a numeric batch budget (~7 tasks, > ~8 tasks triggers sub-agents). Guidance is fully executable without reading anything else for the core loop.

Workflow Clarity

The Specify → Design → Tasks → Execute pipeline is sequenced with an auto-sizing matrix, per-gate validation scripts, an explicit feedback loop ('A non-zero exit means STOP and fix before proceeding'), a safety valve for wrongly skipped phases, a bounded fix→re-verify loop (3 iterations), and blast-radius limits on destructive operations. This matches the anchor-5 pattern of clear sequence, explicit validation, and error-recovery loops.

Progressive Disclosure

All 12 references linked in the body exist in references/ and are signaled one level deep via inline links plus two trigger-pattern→file tables, and the 5 scripts are real and consistently addressed via <skill-dir>. Slightly below the top anchor because the 'Sub-Agent Delegation' section inlines substantial mechanics (batch packing rules, Verifier's 5 steps) that are also the stated content of sub-agents.md — a minor organization gap where the overview carries reference-level detail.

Specificity

Lists multiple concrete, verifiable capabilities: 'Writes testable requirements in EARS notation, atomic tasks, atomic Conventional Commits, and requirement traceability', 'Ships deterministic Python validation scripts', 'independent Verifier (author != verifier, evidence-or-zero), a discrimination sensor, a decision log (STATE.md)'. Coverage of the skill's actions is comprehensive, matching the anchor-5 example's breadth.

Completeness

Explicitly answers both questions: what ('Feature planning and implementation with 4 adaptive phases... deterministic Python validation scripts...') and when ('Use when (1) planning features, (2) implementing with verification and atomic commits, (3) validating an implementation against a spec'), plus a negative scope clause ('Do NOT use for pure architecture decomposition analysis'). This mirrors the anchor-5 example structure exactly.

Trigger Term Quality

Trigger phrases are natural user utterances with good synonym coverage: 'specify feature', 'discuss feature', 'implement', 'validate', 'verify work', 'UAT', 'record decision', 'pause work', 'resume work'. Both lifecycle verbs and colloquial variants are present, satisfying the comprehensive-coverage anchor.

Distinctiveness Conflict Risk

The spec-driven niche and the explicit 'Do NOT use for...' exclusion make it mostly distinct, but the single-word triggers 'design', 'tasks', 'implement', and 'validate' are generic and could fire for unrelated requests, giving minor overlap risk with general coding-workflow skills. Not 5 because those bare-word triggers are broader than the clear-niche anchor; not 3 because the negative-scope clause and domain framing substantially disambiguate it.