Conciseness

The ~34-line body is pure numbered instruction with no concept-teaching and fully assumes Claude's competence. It is not anchor 5 ("every token earns its place") because the opening "Read the relevant development guidelines before starting your task" and the closing "This step is mandatory before writing any code" are redundant bookends restating the description and step 1.

Actionability

Three copy-paste-ready commands with exact paths ("python3 ./.trellis/scripts/get_context.py --mode packages", "cat .trellis/spec/<package>/<layer>/index.md", "cat .trellis/spec/guides/index.md") plus explicit selection criteria with examples (backend, frontend, unit-test, docs) and named guideline files. Fully executable guidance covering the common cases — anchor 5.

Workflow Clarity

Steps 1–6 are clearly numbered and sequenced, with a checklist-driven decision point ("Follow the Pre-Development Checklist section") and an anti-failure guard ("The index is NOT the goal"). It falls short of anchor 5 because there is no explicit checkpoint confirming all relevant guideline files were read before proceeding to step 6 — a minor validation gap, not the missing-sequence or absent-validation issues of anchors 2–3.

Progressive Disclosure

Per the rubric's simple-skill note, a sub-50-line skill with no need for external references scores 5 with well-organized sections: the numbered bold-headed steps and sub-bullets are clear, and the skill correctly points to external project spec content rather than inlining it. No bundle files exist, so there is no nested-reference risk.

Specificity

"Discovers and injects project-specific coding guidelines from .trellis/spec/" and "Reads spec indexes, pre-development checklists, and shared thinking guides" list several concrete actions anchored to a specific path. This matches anchor 4 (several specific actions, minor gaps) rather than 5, because it never states how the discovered guidelines are applied, leaving slight coverage gaps.

Completeness

The what is explicit ("Discovers and injects... Reads spec indexes, pre-development checklists, and shared thinking guides") and the when is an explicit "Use when..." clause with four concrete trigger phrases. This matches anchor 5 exactly; anchor 4's "when could be more explicit" does not apply since multiple concrete triggers are enumerated.

Trigger Term Quality

Triggers "starting a new coding task, before writing any code, switching to a different package, or needing to refresh project conventions and standards" are natural phrases users would say, supplemented by the ".trellis/spec/" path. Good coverage but not anchor 5's comprehensive synonym/extension list — standalone terms like "trellis" or "read the specs" are absent.

Distinctiveness Conflict Risk

The ".trellis/spec/" niche and spec-reading workflow are clearly distinct, but broad timing triggers like "before writing any code" and "starting a new coding task" could overlap with general development-workflow skills. Mostly distinct with minor overlap risk (anchor 4), not anchor 5's minimal-conflict clear niche.