The body is a ~300-line prose document that, while dense with non-obvious domain heuristics ("Thirty to fifty events is the sweet spot", "Bracket retention over N-day for stability"), also explains concepts Claude already knows ("Retention is repeat behavior over time", "Funnels measure progression through a sequence", "A cohort is a group of users sharing an attribute or behavior") and opens with narrative setup. It is not a 3 because it is long and includes framing explanations that could be trimmed; it is not a 1 because there is no generic filler padding and most tokens carry specific domain judgment.

Concrete, specific, actionable guidance throughout — "Past tense, action-oriented", "Object-action format", "snake_case", "Append `_v2` to events when semantics change", "Keep old events firing during the transition (90 days is typical)" — with concrete examples (`checkout_completed`, `subscription_tier`, NSMs like Figma's weekly active editors). It is not a 2 because guidance is complete and specific rather than vague or pseudocode; per the scoring notes, absence of code in an instruction-only skill is not penalized when guidance is this actionable.

A clear sequence exists ("The instrumentation hierarchy" bottom-up stack and the numbered "12 considerations" framework), but validation/verification checkpoints are implicit or missing — the schema-migration pattern (fire both versions, migrate dashboards, deprecate v1) has no explicit "verify then proceed" step. It is not a 3 because explicit validation steps and error-recovery feedback loops are absent for batch/migration operations, which the rubric caps at 2; it is not a 1 because the multi-step sequence is clearly laid out.

Structure is strong — an overview body, inline "Detail in [`references/…`]" pointers per section, and a dedicated "Reference files" index — but the body references `references/retention-measurement-patterns.md` (retention section) which is NOT present in the bundle, so navigation to that detail fails. It is not a 3 because, scored against the actual bundle structure as the rubric directs, one referenced path is broken; it is not a 1 because references are one level deep, clearly signaled, and the index itself lists only the 9 files that actually exist.

Lists many concrete capabilities in one breath — "Event taxonomy, property design, naming conventions, schema versioning, identity stitching, funnel design, retention cohorts, North Star metric selection, dashboard hygiene, instrumentation debt" — matching the anchor for multiple specific concrete actions. It is not a 2 because the catalog is comprehensive rather than naming only a domain and a few actions; voice is third person ("How to actually instrument…"), so no specificity penalty applies.

Explicitly answers both what ("How to actually instrument product analytics correctly…") and when via an explicit "Triggers on…" / "Also triggers when…" clause, satisfying the anchor for both what AND when with explicit triggers. It is not a 2 because the trigger guidance is explicit rather than merely implied.

Extensive natural-term coverage — "product analytics setup, event taxonomy, tracking plan, instrumentation, Mixpanel setup, Amplitude setup, PostHog setup, warehouse-native analytics" plus the colloquial "team has data but cannot trust it" — terms a user would actually say. It is not a 2 because common variations and tool names are well covered, not just a single keyword.

Triggers are specific to instrumentation execution (tracking plan, schema versioning, Mixpanel/Amplitude/PostHog setup, instrumentation debt), carving a clear niche unlikely to fire for strategy or experimentation skills. It is not a 2 because the trigger set is distinctive and tool/event-instrumentation specific rather than a generic overlap-prone phrase.