Conciseness

The ~28-line body is lean and every section carries decision guidance — tool names, per-platform behavior notes, split logic, and guardrail rules — with no explanation of concepts Claude already knows. 'Real history for this advertiser is the truth' is the only arguably padded line, but it reinforces the skill's core rule, so this fits the 5 anchor ('every token earns its place') better than the 4 anchor's 'minor instances of over-explanation'.

Actionability

Concrete elements exist — named tools (`pull_google_ads_performance`, `pull_meta_ads_performance`, `forecast_campaign`), per-platform behavioral direction, and handoffs to named skills — but the key detail the skill exists for is missing: not a single actual CPM/CPC/CPA range is provided despite the promise of 'typical CPM, CPC, and CPA ranges per platform'. This matches the 3 anchor ('some concrete guidance but incomplete; missing key details'); it is not a 2 because the guidance that is present (tool calls, rules, handoffs) is specific and executable rather than high-level hints.

Workflow Clarity

A clear sequence is present — 'Before quoting a range, pull what this account already does', then platform behavior, then 'Show the split with a rationale and projected CPA per channel', then handoff to media-plan and launch — with the Rules section acting as guardrails. Not a 5 because there are no explicit validation checkpoints (e.g., how to cross-check a projected CPA against the account's own history), and not a 3 because the ordering cues are explicit rather than implicit and the skill involves no destructive or batch operations that would demand feedback loops.

Progressive Disclosure

The skill is under 50 lines, has no bundle files (references/, scripts/, assets/ are absent), and needs none for its current scope; it is organized into five well-labeled sections with clear cross-skill pointers (media-plan, launch) that are one level deep. Per the simple-skill guideline, this earns a 5; the missing benchmark data itself is scored under actionability, not structure.

Specificity

Names two concrete capabilities — 'Ground channel-mix and budget-split decisions in typical CPM, CPC, and CPA ranges per platform' and 'set realistic performance expectations' — with precise metric vocabulary (CPM/CPC/CPA). It is not a 5 because coverage is limited to those two actions without enumerating more of the skill's scope, and not a 3 because the actions are more specific than the '1-2 concrete actions' anchor example.

Completeness

Explicitly answers both parts: the 'what' ('Ground channel-mix and budget-split decisions in typical CPM, CPC, and CPA ranges per platform') and the 'when' with a concrete 'Use when' clause listing three specific trigger scenarios. This matches the 5 anchor, which requires both what and when with concrete trigger phrases.

Trigger Term Quality

Includes natural user phrasings like 'what to expect on a platform', 'how to split budget across channels', and 'whether their numbers are normal'. Not a 5 because obvious trigger synonyms such as 'benchmarks', 'are my CPMs/CPCs good', or 'media plan' are absent; not a 3 because the phrases present go well beyond a bare 'Works with PDF files'-level keyword.

Distinctiveness Conflict Risk

The ad-platform benchmark niche (CPM/CPC/CPA ranges, channel-mix, budget-split) is distinct with clear triggers. Not a 5 because it could overlap with closely related media-planning or campaign-management skills — the body itself hands off to a 'media-plan' skill — so minor overlap risk remains.