Conciseness

The body avoids explaining concepts Claude already knows and uses dense tables/templates, but redundancy is noticeable rather than minor: the Interactive Mode section (~30 lines) restates the trigger table and Update Process Step 1 questions, the classification table has near-duplicate rows ("Project Convention" vs "Convention"), the Code-Spec vs Guide distinction is explained three separate times, and the closing "Core Philosophy" section is motivational padding. This matches "mostly efficient but includes some unnecessary explanation or could be tightened" rather than the minor-trims bar of score 4.

Actionability

Concrete guidance throughout: exact directory layout, an executable command ("cat .trellis/spec/<category>/<file>.md"), a classification table mapping learning type to action, and copy-paste-ready markdown templates for each update type. Per the scoring note, absence of runnable code in an instruction-only skill is not penalized since the guidance is actionable. It falls short of score 5 because templates contain unfilled placeholders ("// How it's implemented" + "code example") with no fully worked example of a completed spec update and no concrete example file paths (e.g., .trellis/spec/backend/error-handling.md).

Workflow Clarity

The Update Process is a clearly sequenced 5-step flow (identify → classify → read target spec → update → update index) with checkpoints: Step 3 mandates reading the existing spec before editing, and the post-update Quality Checklist ("Does it duplicate existing content?", "Is it in the right code-spec file?") validates before finishing. It does not reach score 5 because there is no validate→fix→retry feedback loop, and the parallel decision frameworks (Interactive Mode plus multiple overlapping tables) dilute the single canonical sequence.

Progressive Disclosure

No bundle files exist; the entire skill is a single 357-line file. Section headers and organization are good, but the ~140-line template library is exactly the inline content the score-3 anchor describes (analogous to its "200 lines of API reference that could be in a separate file" example), and the under-50-line simple-skill exception clearly does not apply. Not score 2 since structure is strong, not score 4 since at this length, with no references at all, the templates belong in a references/templates.md with SKILL.md kept as an overview.

Specificity

"Captures executable contracts and coding conventions into .trellis/spec/ documents" names the domain and 1-2 concrete actions with a specific target location, but the description relies on a single action verb ("captures") and does not enumerate the several operations the skill actually performs (classify, template, index). It matches the anchor "Names domain and 1-2 concrete actions, but not comprehensive" — more concrete than the score-2 anchor, less enumerative than score 4.

Completeness

The description clearly answers both questions: what ("Captures executable contracts and coding conventions into .trellis/spec/ documents") and when (an explicit "Use when..." clause listing three concrete trigger contexts: debugging, implementing, discussion). The when-clause is explicit with concrete trigger phrases, exceeding the score-4 example in specificity.

Trigger Term Quality

"Use when learning something valuable from debugging, implementing, or discussion" provides natural trigger phrases covering the three main learning contexts. Good keyword coverage, but common variations the body itself surfaces ("fixing a bug", "convention", "gotcha", "spec update") are absent, keeping it short of comprehensive synonym coverage.

Distinctiveness Conflict Risk

The ".trellis/spec/" target and "executable contracts" framing establish a clear niche distinct from generic documentation skills, but the broad learning-capture phrasing ("learning something valuable... that should be preserved for future sessions") carries minor overlap risk with other knowledge-persistence/memory skills. Mostly distinct with minor overlap risk.