Conciseness

The body is dense with domain-specific artifacts — risk/frequency tables, severity/response-time tables, a copy-paste finding template, checklists, and script commands — with zero padding on concepts Claude already knows (it never explains what ISO 27001 or an audit is). The only trimmable tokens are the 8-line Table of Contents and the opening line that restates the description, which is too minor to drop below the anchor-5 'every token earns its place' level.

Actionability

Mostly concrete: executable script invocations ('python scripts/isms_audit_scheduler.py --year 2025 --output audit_plan.json'), a fill-in finding documentation template, specific response times (30/90 days), and Stage 1/2 checklists. However, a few steps stay high-level — 'Define sample size based on population and risk' gives no actual sample-count guidance, and 'Test control design (does it address the risk?)' offers a question rather than a procedure (detail is delegated to security-control-testing.md). These minor gaps fit anchor 4 rather than the fully-executable anchor 5.

Workflow Clarity

Every multi-step workflow ends with an explicit bolded checkpoint ('**Validation:** Audit plan covers all Annex A controls within certification cycle', '**Validation:** All controls in scope assessed with documented evidence'), the corrective-action workflow embeds a genuine feedback loop ('5. Auditor verifies effectiveness of corrections / 6. Finding closed with evidence of resolution'), and Stage 1/2 preparation use checkbox checklists — matching anchor 5's requirement for explicit validation steps, feedback, and checklists. Anchor 4 ('minor validation gaps') understates the consistency of the checkpoints.

Progressive Disclosure

Good structure overall: the body stays at overview level, three reference files are clearly signaled both inline ('see [security-control-testing.md](references/security-control-testing.md)') and in a References table with content summaries, and all references are verified one level deep (internal anchors only). The gap: references/ contains a fourth file, iso27001_audit_playbook.md (the largest, with a 7-phase audit workflow), that is never mentioned anywhere in SKILL.md, so its content is undiscoverable — a real but bounded organization gap consistent with anchor 4 rather than the fully-clean anchor 5.

Specificity

The description lists seven concrete, distinct actions covering the full audit lifecycle: 'review control implementation evidence, document audit findings, classify nonconformities, generate risk-based audit plans, map controls to Annex A requirements, prepare Stage 1 and Stage 2 audit documentation, and support corrective action workflows'. This is comprehensive coverage, matching the anchor-5 example's breadth rather than the 'minor gaps' of anchor 4 — no major audit-lifecycle capability is missing.

Completeness

It explicitly answers both questions: the 'what' opens with 'compliance verification, security control assessment, and certification support' plus a third-person action list, and the 'when' is an explicit 'Use when the user mentions...' clause with concrete trigger phrases — mirroring the anchor-5 example structure. Anchor 4 ('when could be more explicit') does not apply since the trigger list is explicit and enumerated.

Trigger Term Quality

The 'Use when' clause enumerates exactly the phrases a user needing this skill would naturally say: 'ISO 27001, ISMS audit, Annex A controls, Statement of Applicability (SOA), gap analysis, nonconformity management, internal audit, surveillance audit, or security certification preparation', including the SOA acronym expansion as a synonym. Coverage is comprehensive with synonyms; at most one or two variants (e.g., 'recertification') are absent, which does not drop it to anchor 4.

Distinctiveness Conflict Risk

It occupies a clear niche — ISO 27001 ISMS auditing — with distinct, framework-specific triggers (Annex A, SOA, surveillance audit, Stage 1/Stage 2) that a generic security-review or SOC 2 skill would not claim. 'security control assessment' is mildly generic but is anchored to the ISO 27001 context throughout, so conflict risk is minimal per the anchor-5 example.