Conciseness

The body is dense and mostly earns its tokens: "Verify before you report — false positives are the cardinal sin", the severity table with concrete examples ("auth bypass (`jwt.decode` not `verify`)"), and the report template all add non-obvious guidance with no explanation of concepts Claude already knows. Not 5 because the "Base Framework" block largely duplicates the "Evidence, secrets, and execution safety" section, and the "Optional Workflow Integration" and "Portability note" sections are peripheral scaffolding that could be trimmed or offloaded to references.

Actionability

For an instruction-only skill the guidance is fully concrete: 11 sequenced phases each enumerating exact checks ("missing object-level checks (IDOR)... every query scoped to the session's tenant, RLS correctness"), worked micro-examples ("an unauthenticated attacker can set `role=admin` in the signup body because the handler passes `req.body` straight to `User.create`"), named tools per task (Semgrep, Gitleaks, `npm audit`, Trivy), and a complete copy-paste-ready report template. Specific examples cover the common audit cases.

Workflow Clarity

Clear ordered sequence ("Work the phases in order — understand and model before you judge, verify before you report") with explicit validation checkpoints and feedback loops: trace source→sink before reporting, "If you cannot verify... report it as a question", "Each CRITICAL and HIGH finding must be individually traced", assumptions made explicit with conditional findings, and "Read the target end-to-end once before flagging anything". Error-recovery paths (downgrade or drop unprovable findings, conditional-on-absent-mitigation framing) are explicit throughout.

Progressive Disclosure

Structure against the actual bundle is excellent for the 13 references/*.md files: one level deep, each inline-linked at its phase ("read a reference when its phase begins and the target actually touches that domain, and skip references the target never touches") plus a consolidated "Reference map" table, and spot-checks confirm the files exist with real content. Not 5 because the "Required packaged policies" section links 10 `shared/base/*.md` files plus `shared/workflow-contract.md` that do not exist anywhere in the bundle — 11 dangling links that break navigation.

Specificity

Quotes: "Conduct a security-led audit of code, systems, APIs, infrastructure, dependencies, and AI workflows", "with threat modeling and exploitability-backed remediation" — several concrete actions (audit, threat modeling, remediation) across six named target domains. Not 5 because the capability list stops short of the full deliverable set (severity rating, findings report, production-readiness verdict); not 3 because it goes beyond 1-2 actions with explicit domain coverage.

Completeness

What: "Conduct a security-led audit... with threat modeling and exploitability-backed remediation"; When: "Use when security risk is the primary concern", plus negative triggers "Do not use for a generic code review, database design, or non-security debugging". Both are explicit, so above 3; not 5 because the when-clause is an abstract condition rather than concrete trigger phrases a user would actually utter (e.g., "when the user mentions vulnerabilities or asks for a security review").

Trigger Term Quality

Quotes: "security-led audit", "threat modeling", "code review", "infrastructure", "dependencies", "AI workflows" — natural terms users would plausibly say. Not 5 because common synonyms like "vulnerability", "security review", "pentest", or "hardening" are absent; not 3 because coverage extends well beyond a couple of generic keywords with several domain-specific variations.

Distinctiveness Conflict Risk

Quotes: "Use when security risk is the primary concern. Do not use for a generic code review, database design, or non-security debugging" — a clear security-audit niche with explicit negative triggers that disambiguate the closest competing skills. Minimal conflict risk; matches the anchor for a clear niche with distinct triggers.