Conciseness

The body is dense with non-derivable project-specific knowledge (index names, file paths, failure cases) and never explains generic concepts, but most steps run 5-10+ lines with embedded anecdotes (e.g. "a real case: a single-device DB fixture passed against both the buggy and the fixed code") and long parenthetical asides that could be cut roughly in half without losing the instruction. It is not a 2 because nothing is generic padding, and not a 4 because substantial tightening is possible throughout steps 3, 7, and 10.

Actionability

For an instruction-only skill the guidance is fully executable: concrete commands ("Grep `CREATE INDEX` for *every* index", "`EXPLAIN QUERY PLAN` at a realistic row count"), real artifacts ("`test/db_test_helpers.py` fixtures", "`server/scan/presence.py`", "`idx_currentscan_scanmac`"), an exact save path, and a per-section document template. Specific examples cover the common cases, matching the 5 anchor.

Workflow Clarity

Thirteen clearly sequenced steps with explicit validation checkpoints ("confirm it fails for the right reason", the dedicated final-check pass in step 11, the implementation checklist) and error-recovery feedback loops ("the correct recovery is to actually revert the implementation, confirm the test fails red against the reverted code, and only then reapply the fix"). This matches the 5 anchor's explicit validation, feedback loops, and checklists.

Progressive Disclosure

Everything lives in one ~75-line/18KB SKILL.md with no bundle files or references at all — the multi-sentence war stories (the `sse_manager.js` indicator saga, the DB-fixture case) and the codebase-specific catalog (index names, API surface paths) are inlined where a references file would keep the overview lean. It is not a 4 because no content is split out at all, and not a 2 because section structure is clear and nothing is buried or nested.

Specificity

The description enumerates seven concrete, distinct actions — "challenging the idea before designing it", "verifying every claim against actual code", "tracing every downstream consumer of a new mechanism", "evaluating performance impact against the schema/indexes that actually exist", "recording rejected alternatives and open-issue decisions", and "a dedicated final-check pass" — giving comprehensive coverage of the skill's process. It is not a 4 because coverage is comprehensive rather than having minor gaps, and it uses third-person voice throughout.

Completeness

"Read before writing a PRD, design doc, or feature proposal" is an explicit when-clause with concrete trigger phrases, and "Covers challenging the idea... a dedicated final-check pass" explicitly enumerates the what. Both questions are answered clearly and explicitly, matching the 5 anchor; the 4 anchor's weaker 'when' does not apply.

Trigger Term Quality

"writing a PRD, design doc, or feature proposal" provides good natural keyword coverage — phrases users would actually say. It is not a 5 because common synonyms and variations ("product requirements document", "spec", "RFC") are missing, but it clearly exceeds the 3 anchor's 'some relevant keywords'.

Distinctiveness Conflict Risk

PRD/design-doc/feature-proposal authorship is a clear niche with distinct, domain-specific triggers, so conflict risk with other skills is minimal. It is not a 4 because the triggers ("PRD", "design doc", "feature proposal") directly and uniquely name this domain rather than overlapping generically with related skills.