Conciseness

The 'why case matters' explanation appears three times (intro paragraph, Quick Reference bullets "Most web servers treat /Page and /page as different URLs", and the Explain section), and the Check section largely duplicates Code Review. Mostly efficient overall with tight, short sections, so anchor 3 (could be tightened) fits better than 2 (several padded sections) or 4 (only minor trimmable excess).

Actionability

Concrete, executable signals like "verify they return 301 to the lowercase version, not 200" and "Check the sitemap for any uppercase <loc> entries" give specific pass/fail criteria, with framework code correctly deferred to the reference. Not 5 because the body contains no copy-paste commands or snippets of its own; not 3 because the guidance is specific and directly executable, not vague direction.

Workflow Clarity

A clear check→fix→verify sequence: scan for uppercase (Check), normalize routing and add 301s (Fix), then verify redirect status and sitemap (Code Review). Minor gaps — no numbered steps and no explicit re-validation loop — keep it at anchor 4 rather than 5, and verification signals are far too specific for 3.

Progressive Disclosure

The body is a concise overview and points one level deep to `references/rule.md` ("For full implementation details, code examples, and framework-specific guidance"), which exists and holds the nginx/Apache/Next.js/Express code. Nothing that belongs in the reference is inlined, so it matches the anchor 5 pattern (clear overview, well-signaled one-level references).

Specificity

"auditing URL structure or configuring a new site's routing" names the domain plus two actions, but the description never states the skill's core action — enforcing lowercase URLs or redirecting mixed-case variants. It matches anchor 3 (domain and 1-2 concrete actions, not comprehensive) rather than 4, which would require several specific actions with only minor gaps.

Completeness

The "when" is explicit ("Use when auditing URL structure or configuring a new site's routing"), but the "what" is vague — nowhere does it say the skill enforces lowercase URLs; the closest hint is the parenthetical about case-insensitive file systems. Scoring only what is explicit, this sits between anchor 3 (what unclear) and 4 (both present), closer to 3 because the core capability must be inferred.

Trigger Term Quality

Relevant keywords are present ("URL structure", "routing", "case-insensitive file systems"), but the most natural user phrases — "lowercase URLs", "URL case", "SEO", "duplicate content" — are absent. This fits anchor 3 (some relevant keywords, missing common variations) rather than 4, since a user asking about lowercase URLs specifically would not trigger this description.

Distinctiveness Conflict Risk

The framing "Applies to any server or framework that allows case-insensitive file systems (Linux servers are case-sensitive by default)" carves out a distinct niche. Not 5 because "auditing URL structure" is broad enough to overlap with canonical-URL, redirect, and general routing skills; not 3 because the case-sensitivity qualifier meaningfully disambiguates it.