Conciseness

The ~90-line body is lean and assumes Claude's competence: no explanation of what WordPress or PHP is, no padding. Dense, non-obvious content like the responsibility table and the authority-separation rules ("reading media metadata does not grant bytes, moderation does not grant deletion") earns every token. It matches the 5 anchor, not 4, because no sections need trimming.

Actionability

For an instruction-only skill the guidance is fully concrete: an exhaustive WordPress-to-EmDash responsibility table with specific APIs and capabilities ("ctx.http.fetch() with network:request and an allowedHosts entry", "cron hook and ctx.cron scheduling", "ctx.settings; declare credentials as encrypted secret fields"), plus explicit decision rules for sandboxed vs. trusted native format. Per the rubric's code-vs-instruction note, the absence of code is not penalized when the guidance is this actionable, and the specific examples cover the common cases.

Workflow Clarity

A clear six-phase sequence (Understand the source → Assign each responsibility → Choose the plugin format → Plan data movement → Verify equivalent behavior → Deliver the port) with explicit validation checkpoints: report missing source/target gaps instead of inventing equivalents, make imports restartable with duplicate detection, and a dedicated verification section plus a delivery checklist. Batch migration work does include validation, so the destructive/batch cap does not apply.

Progressive Disclosure

The SKILL.md is a decision-level overview that pushes API detail to sibling skills, clearly signaled and conditionally loaded ("Load [creating-plugins]... before implementing plugin code. Load [building-emdash-site]... when the port changes collections, seeds, queries, or frontend templates"). References are one level deep with no nesting; the skill is self-contained for its scope. (Sibling files are not resolvable in this evaluation sandbox — a harness artifact — but the reference design itself is exemplary, so it matches the 5 anchor rather than 4.)

Specificity

The description lists multiple specific concrete actions — "Analyze and port WordPress plugin behavior, custom post types, shortcodes, admin workflows, and stored data to current EmDash extension points" — with comprehensive coverage of the domain. It matches the 5 anchor (multiple specific actions, comprehensive) rather than 4, since no significant capability area is missing.

Completeness

Both what ("Analyze and port ... to current EmDash extension points") and when ("Use for WordPress-plugin migrations or when deciding which behavior belongs in an EmDash plugin, site schema, seed, or Astro code") are explicit, with a concrete negative boundary ("Do not use for visual theme ports without plugin functionality"). This clearly matches the 5 anchor rather than 4, where 'when' would be less explicit.

Trigger Term Quality

Good natural-term coverage: "WordPress plugin", "WordPress-plugin migrations", "port", "custom post types", "shortcodes" are phrases a user would actually say. A few natural variations (e.g. "move/migrate my WordPress plugin to EmDash") are only weakly implied by "migrations", so it sits at the 4 anchor rather than 5.

Distinctiveness Conflict Risk

Clear niche (WordPress-to-EmDash plugin migration) with distinct triggers and an explicit exclusion clause that prevents firing on visual theme ports. Minimal conflict risk with other skills; matches the 5 anchor.