Conciseness

Lean and efficient throughout: no concept explanations Claude already knows, rationale offloaded to "references/why-single-pass.md", and every section carries operational weight (mode table, persona contract, grounding actions, steelman template, output format, hard rules). The apparent duplication between persona rules and hard rules 4/6 is handled via explicit cross-references ("(persona rule 2)"), not restated content, so it sits at anchor 5 rather than anchor 4's 'minor instances that could be trimmed'.

Actionability

Highly concrete guidance: verbatim persona blockquote, exact mode-declaration line ("Mode: critical/<mode>. Target: <one-line summary>."), per-mode grounding commands ("`Read` the `plan.md`; `grep` for at least two referenced files/symbols"), and a copy-paste output template with classification definitions. It stops short of anchor 5 because the taxonomy walk — the core procedure — depends on "rules/taxonomy-plan.md", "rules/taxonomy-code.md", "rules/taxonomy-analysis.md", and "rules/deep-mode.md", none of which exist in the bundle, so the run cannot actually execute that step as delivered; this is more than the 'covers the common cases' bar of anchor 5 but the in-body guidance itself is fully executable, above anchor 3.

Workflow Clarity

The sequence is clear and ordered by signal phrases ("State the detected mode in one line before running", "Before writing the findings, run at least one grounding action", "Walk the failure taxonomy", output format last) and includes real validation checkpoints — grounding failures escalate to must-fix findings ("A referenced file, symbol, or path that does not resolve is itself a `must-fix` finding") and "Skipped rows are listed, never skipped silently". It is not anchor 5 because there is no single consolidated ordered step list; the run order must be assembled from several sections, a minor gap versus anchor 5's explicit checklists.

Progressive Disclosure

The design is anchor-5 quality — a concise overview with well-signaled, one-level-deep references, each annotated with its contents ("procedure, lens catalog, single-context fallback, sub-agent prompt contract, synthesis, and output format") — but scored against the actual bundle, 4 of the 5 referenced paths (all four "rules/*.md" files) do not exist; only "references/why-single-pass.md" resolves. Since the primary disclosure mechanism (offloading taxonomy and deep-mode detail to rules files) is broken in the delivered bundle, it cannot score above anchor 3's 'some structure' despite excellent signaling.

Specificity

Multiple concrete capabilities and constraints are enumerated: "Adversarial pre-mortem of a plan, code change, or bug diagnosis", "cited findings over a fixed failure taxonomy plus a mandatory steelman", "never scores or fixes, one pass per run", "`deep` runs 3–5 parallel persona lenses", plus the three modes. Coverage of what the skill does, does not do, and how it can be parameterized is comprehensive, matching the anchor-5 example's breadth of concrete actions; it is not anchor 4 because no meaningful capability is left unspecified.

Completeness

Both halves are explicit: what it does ("cited findings over a fixed failure taxonomy plus a mandatory steelman; never scores or fixes, one pass per run") and when to use it ("triggers on ...", with modes and defaults enumerated). This matches the anchor-5 pattern of a concrete 'what' followed by explicit trigger phrases; anchor 4 would require the 'when' to be less explicit.

Trigger Term Quality

Good natural-phrase coverage: "triggers on 'critical', 'challenge this', 'pre-mortem', 'red-team this', 'deep critical review', 'review from every angle', '/critical'" — these are phrases a user would naturally say. It falls short of anchor 5 because common variants like "devil's advocate", "poke holes in this", "what could go wrong", or "stress-test this plan" are missing, but it is well above anchor 3's 'some relevant keywords'.

Distinctiveness Conflict Risk

The niche is well carved out — "pre-mortem", "red-team this", and the explicit "never scores or fixes" cleanly separate it from scoring/review/fix skills. Minor overlap risk remains with general review skills via the broad triggers "critical" and "review from every angle", which a user might also say when they want an ordinary code review, so it is mostly distinct rather than anchor 5's minimal-conflict profile.