The body is lean and assumes Claude's competence — it never explains what marketing is and uses compact tables and bulleted lists (by stage/budget/timeline) with every token earning its place, matching the level-3 anchor.

It provides concrete guidance via numbered ideas, named tactics, a 4-step usage sequence, and a precise Output Format template specifying the exact fields per recommendation (Idea name, Why it fits, How to start, Expected outcome, Resources needed).

The 'How to Use This Skill' section gives a clear, unambiguous sequence (context check → ask → suggest 3-5 → implementation details → consider resources); for a non-destructive advisory skill, validation checkpoints are not required, so it meets the level-3 bar.

SKILL.md is a clear overview with a single well-signaled one-level-deep reference (references/ideas-by-category.md) that exists on disk; the full idea list is appropriately split into that file while the overview table stays inline, giving easy navigation.

It names a clear domain (marketing for SaaS/software) and a concrete deliverable ("provides 139 proven marketing approaches organized by category"), but describes a single catalog deliverable rather than multiple distinct processing actions like 'extract, fill, merge,' so it stops short of the level-3 anchor.

Explicitly answers both 'what' (provides 139 proven marketing approaches organized by category) and 'when' with an explicit 'Use when' clause listing concrete triggers, matching the level-3 anchor.

Strong coverage of natural phrasings users would actually say: 'marketing ideas,' 'growth ideas,' 'how to market,' 'marketing strategies,' 'marketing tactics,' 'ways to promote,' and 'ideas to grow.'

Scoped to SaaS/software product marketing with specific trigger phrases, giving it a clear niche unlikely to conflict with unrelated skills.