Conciseness

Every line carries non-obvious domain guidance — the tool name, "longevity alone does not establish profitability", "absence is opportunity", the trademark risk of copying — with zero concept explanation or padding. This matches anchor 5 (lean, assumes Claude's competence, every token earns its place); anchor 4 would require trimmable over-explanation, of which there is none.

Actionability

Concrete guidance throughout: the named tool `research_campaign_opportunity`, an explicit fallback ("Ask for public ad-library links or examples when the tool does not return competitor ads"), specific analysis dimensions ("price framing, trial, guarantee, urgency"), and handoff to named skills ("ad-copy-generation or **launch** skill"). It stops short of anchor 5 because the fallback names no specific ad libraries and no worked example covers a common case, while clearly exceeding anchor 3's pseudocode-level guidance.

Workflow Clarity

The three numbered phases (find what they run → read the pattern → turn it into your move) form a clear sequence, with an error-recovery checkpoint in step 1 and a validation rule ("Separate what is proven... from what is a test") in Rules. The skill is read-only so the destructive/batch validation cap does not apply, and the simple-skill exception holds for this under-50-line single-task skill with an unambiguous process — matching anchor 5 rather than anchor 4's 'minor validation gaps'.

Progressive Disclosure

The skill is under 50 lines with no bundle files (no references/, scripts/, or assets/ exist) and no content that warrants external files; it is organized into four well-labeled sections (## 1, ## 2, ## 3, ## Rules) and only points to other skills, not nested documents. Per the rubric's guideline for short skills needing no external references, this matches anchor 5.

Specificity

"Research competitors' advertising — the creative they run, their angles and offers, and where they compete for the same auctions" enumerates several concrete research targets (creative, angles, offers, auction presence), but rests on a single action verb rather than multiple distinct actions. It exceeds anchor 3 (which covers only 1-2 concrete actions) but falls short of anchor 5's multiple specific actions with comprehensive coverage.

Completeness

The description explicitly answers both: what ("Research competitors' advertising — the creative they run, their angles and offers, and where they compete for the same auctions") and when ("Use when a user wants competitive research, creative inspiration, to see what rivals are running, or market positioning for ads") with concrete trigger phrases. This matches anchor 5 exactly; anchor 4 would require the 'when' clause to be less explicit or specific.

Trigger Term Quality

"competitive research", "creative inspiration", "to see what rivals are running", "market positioning for ads" are natural phrases users would say. A few common variations are missing (e.g., "competitor ads", "ad library"), so it matches anchor 4 rather than anchor 5's comprehensive synonym coverage, and is clearly above anchor 3's partial keyword coverage.

Distinctiveness Conflict Risk

"competitors' advertising", "the same auctions", "rivals", "ads" carve out a clear niche in ad competitive research with distinct triggers. Minor overlap risk remains with closely related ad skills via the "creative inspiration" and "market positioning" triggers, so anchor 4 fits better than anchor 5's minimal-conflict bar.