Conciseness

The body is dominated by dense tables and copy-paste SQL with almost no prose padding and no explanation of concepts Claude already knows. It misses anchor 5 because of clear redundancy: the 'When to Activate' section (lines 16-22) and the 'When to Use This Skill' section (lines 150-157) are near-duplicate lists, and the closing Supabase credit line duplicates the frontmatter metadata.

Actionability

Every section is executable: concrete CREATE INDEX statements mapped to query patterns, a data-type decision table, complete SQL for composite/covering/partial indexes, RLS, UPSERT, cursor pagination, SKIP LOCKED queue processing, and ready-to-run diagnostic queries against pg_catalog/pg_stat_statements. This matches anchor 5's copy-paste-ready coverage of common cases.

Workflow Clarity

As a quick-reference skill there is no multi-step workflow to sequence, and the 'Configuration Template' performs system-wide, hard-to-reverse changes (ALTER SYSTEM, REVOKE ALL ON SCHEMA public) with no validation or verification steps beyond pg_reload_conf(). Per the rubric's feedback-loops rule for database operations, the missing validate/verify checkpoints cap workflow clarity at 3, overriding the simple-skill exception; it is not lower because no incoherent or misleading sequence exists.

Progressive Disclosure

Sections are clearly organized with headers and tables, but this is a ~150-line monolithic quick reference with no bundle files at all — content that would naturally live in separate references (index cheat sheet, data-type reference, anti-pattern queries, config template) is all inlined in SKILL.md, and pointers to the 'database-reviewer' agent and sibling skills are not file-based references. This matches anchor 3 ('some structure, content that should be separate is inline'); it beats anchor 2 because the inline content is well-sectioned and navigable, and falls short of anchor 4's 'most content appropriately placed' since nothing is split out.

Specificity

The description names concrete capability areas — 'query optimization, schema design, indexing, and security' plus 'anti-pattern detection' — which is several specific items with only minor gaps (e.g., connection pooling and RLS from the body are absent). It falls short of anchor 5's comprehensive action coverage because these are topic areas rather than fully enumerated actions, but exceeds anchor 3's '1-2 concrete actions' bar.

Completeness

The 'what' is clear (patterns for optimization, schema design, indexing, security), but there is no 'Use when...' clause or equivalent trigger guidance anywhere in the description, which caps completeness at 3 per the judging guidelines. This matches anchor 3 ('clear what, when missing') and is above anchor 2 because the 'what' is specific, not vague.

Trigger Term Quality

Good natural keywords: 'PostgreSQL', 'query optimization', 'schema design', 'indexing', 'anti-pattern'. A few common user phrasings are missing — the synonym 'Postgres', 'SQL', 'slow queries', and 'migrations' — so it does not reach anchor 5's comprehensive synonym coverage, but it clearly beats anchor 3's partial keyword set.

Distinctiveness Conflict Risk

'PostgreSQL database patterns' carves a clear niche with a strong discriminator, but the broad coverage of 'schema design' and 'security' creates minor overlap risk with closely related sibling skills the body itself references ('database-migrations', 'backend-patterns'). This fits anchor 4 ('mostly distinct; minor overlap risk') better than anchor 5's minimal-conflict profile.