Conciseness

The body is two lines with zero padding: no concept explanations, no repetition — "Load and follow the shared skill at ~/.agents/skills/grilling/SKILL.md" plus a one-line provenance comment. Every token earns its place and it fully assumes Claude's competence, matching the 'lean and efficient' anchor; the single HTML comment is maintenance metadata, not over-explanation.

Actionability

The only guidance is a pointer to a specific path — concrete as a command, but it contains no substantive instruction on how to grill, fitting 'minimal concrete guidance; missing the specific steps to execute'. It is not a 1 because the instruction is executable rather than vague, and not a 3 because the referenced target does not exist in this environment or in the bundle, leaving no usable guidance at all.

Workflow Clarity

The single step (load and follow the external file) is clearly stated, but there is no checkpoint or fallback for the case where `~/.agents/skills/grilling/SKILL.md` is absent — a real gap since the file is indeed missing here — and the actual grilling workflow is entirely undefined in this document. This matches 'steps present but checkpoints missing' rather than the mostly-checkpointed level 4.

Progressive Disclosure

The reference to `~/.agents/skills/grilling/SKILL.md` is one level deep and clearly signaled, but it points outside the skill bundle to a home-directory path that does not resolve in this environment, and the comment's cited `scripts/agent-harnesses.py` is likewise absent from the bundle. Structure exists but the skill's content is not actually shipped or navigable, which falls between the clearly-signaled level 4 and the broken-navigation level 2.

Specificity

"Grill the user relentlessly about a plan, decision, or idea" names the domain and one concrete action, matching the '1-2 concrete actions, but not comprehensive' anchor. It is not a 4 because it never enumerates what grilling involves (e.g., probing questions, challenging assumptions, surfacing weaknesses), and not a 2 because it goes beyond merely naming the domain.

Completeness

It has both a clear what ("Grill the user relentlessly about a plan, decision, or idea") and an explicit when ("Use when the user wants to stress-test their thinking"), matching the anchor where 'when' could be more explicit. It falls short of a 5 because the second trigger clause defers to undefined "'grill' trigger phrases" instead of stating concrete trigger phrases.

Trigger Term Quality

"stress-test their thinking" and "grill" are natural terms users would say, but the clause "uses any 'grill' trigger phrases" is circular — it never lists those phrases — and common synonyms like 'poke holes', 'devil's advocate', or 'challenge my plan' are missing. This fits 'some relevant keywords but missing common variations or synonyms' rather than the good coverage of a 4.

Distinctiveness Conflict Risk

"Grill the user relentlessly" carves out a fairly distinct confrontational-interrogation niche with its own trigger ('grill', 'stress-test'), so it is mostly distinct with minor overlap risk against general critique/review skills. It is not a 5 because 'stress-test their thinking about a plan' could still plausibly collide with brainstorming or review skills.