The body is mostly concrete code and checklists rather than conceptual padding, but it is ~490 lines with redundancy — each section's "Verification Steps" are re-stated in the final "Pre-Deployment Security Checklist" — and a niche Solana section that not every user needs.

Packed with executable TypeScript, SQL, and bash (zod validation, parameterized queries, httpOnly cookie setup, RLS policies, DOMPurify, rate-limit config, npm audit) that is specific and copy-paste ready, matching the fully-executable anchor.

Each topic carries explicit "Verification Steps" checkboxes, consolidated by a "Pre-Deployment Security Checklist", and a "Security Testing" section with concrete tests — explicit validation checkpoints and checklists for a complex review process.

Headings are well organized, but everything is inline in one ~490-line SKILL.md with no references/ or other bundle files; the per-topic detail could be split into one-level-deep reference files rather than carried inline.

Lists multiple concrete actions — "adding authentication, handling user input, working with secrets, creating API endpoints, or implementing payment/sensitive features" — matching the multi-action anchor rather than the single-domain anchor at 2.

Explicitly answers both: the when via "Use this skill when adding authentication..." and the what via "Provides comprehensive security checklist and patterns", satisfying the explicit-trigger requirement that would otherwise cap at 2.

Uses natural terms a user would actually say ("authentication", "user input", "secrets", "API endpoints", "payment"), giving good coverage rather than the partial coverage scored at 2.

The security niche is clear, but broad triggers like "handling user input" and "creating API endpoints" could plausibly fire for general coding tasks, so it is not yet at the unlikely-to-conflict level of 3.