The body is lean (~40 lines), assumes Claude's competence, and avoids explaining concepts Claude already knows; every line adds directive guidance.

Concrete directives ("Ask exactly one question at a time, then wait", include recommended option marked as recommended, a brief reason) and a named tool (`request_user_input`) give specific, executable guidance for an instruction-only skill.

The interview is clearly sequenced with an explicit feedback loop ("If an answer creates a contradiction or unresolved dependency, ask a follow-up before moving on"), a maintained decision tree, and a defined stop condition plus summary step.

Under 50 lines with no need for external references, the single SKILL.md is well organized into directive paragraphs and a scannable coverage bullet list, satisfying the simple-skill allowance.

The description names a concrete action and method ("Interview the user about a plan or design until reaching shared understanding, resolving each branch of the decision tree") but centers on a single interview action rather than listing multiple distinct concrete actions, matching the score-2 anchor.

It states both what it does (interview to shared understanding, resolve decision-tree branches) and an explicit "Use when..." clause with concrete triggers, satisfying both what and when.

Natural user-facing phrases are well covered: "stress-test a plan", "get grilled on their design", and the literal trigger "grill me" — terms a user would actually say.

The distinctive "grill me" / stress-test-a-plan niche is unlikely to overlap with other skills, giving it a clear trigger with low conflict risk.