Conciseness

The ~30-line body is pure behavioral instruction with no explanations of concepts Claude already knows, and every rule carries direction ("Ask the questions one at a time, waiting for feedback on each question before continuing"). Only minor trims exist — "Asking multiple questions at once is bewildering" and the repetition of "shared understanding" in the opening and closing lines — fitting anchor 4 ("Efficient; minor instances of over-explanation that could be trimmed") rather than anchor 5's every-token-earns-its-place.

Actionability

Guidance is concrete and executable for an instruction-only skill: exact file paths ("check for `CONTEXT-MAP.md` at root first", "`.agents/standards/CONTEXT-FORMAT.md`", "under `docs/adr/`"), an enumerated three-criteria ADR test ("(1) Hard to reverse, (2) Surprising without context, (3) Real trade-off"), and a precise fact-vs-decision rule. Minor gaps keep it at anchor 4: "lazily" is invoked as a convention without definition, and there is no example question/recommended-answer pair.

Workflow Clarity

The process has a clear arc with an explicit feedback loop ("Ask the questions one at a time, waiting for feedback on each question before continuing") and an explicit gate ("Do not enact the plan until I confirm we have reached a shared understanding"), plus event-driven checkpoints for glossary and ADR integration. It stays at anchor 4 rather than 5 because "shared understanding" is never operationalized (no checklist of design-tree branches covered) and the sequence is distributed across paragraphs rather than laid out as steps.

Progressive Disclosure

The skill is under 50 lines, single-purpose, and needs no external references (no references/, scripts/, or assets/ files exist, and none are required); the body is organized into a clear behavioral intro and one well-titled section ("Domain Glossary & Architectural Decision Rules") with numbered sub-rules. Per the rubric's simple-skill guideline, this earns a 5 with just well-organized sections.

Specificity

"Grill the user relentlessly about a plan or design" names the domain (plan/design stress-testing) and one concrete action, matching the anchor "Names domain and 1-2 concrete actions, but not comprehensive". It is not a 4 because it does not list several specific actions (e.g., one-at-a-time questioning, codebase fact lookups, recommended answers), and not a 2 because grilling a plan is a concrete action rather than a generic domain mention.

Completeness

Both parts are explicit: the 'what' ("Grill the user relentlessly about a plan or design") and the 'when' ("Use when the user wants to stress-test a plan before building"). The 'when' includes one concrete trigger phrase but the "'grill' trigger phrases" clause is unspecified, so it fits anchor 4 ('when' could be more explicit) rather than anchor 5's fully concrete trigger list.

Trigger Term Quality

"stress-test a plan before building" and "grill" are terms a user would naturally say, but "uses any 'grill' trigger phrases" is circular and never enumerates the phrases, and common variations like "poke holes in my plan" or "challenge my design" are missing — matching the anchor "Some relevant keywords but missing common variations or synonyms". It is not a 4 because keyword coverage is thin, and not a 2 because the terms present are genuinely natural.

Distinctiveness Conflict Risk

Adversarial plan interrogation is a clear niche with fairly distinct triggers ("stress-test a plan", "grill"), but the broad scope "a plan or design" leaves minor overlap risk with general planning, brainstorming, or design-review skills — matching anchor 4 ("Mostly distinct; minor overlap risk") rather than anchor 5's minimal conflict risk.