Conciseness

The ~55-line body is efficient with no explanation of concepts Claude already knows; anchor 4 fits ('minor instances of over-explanation that could be trimmed') because 'What is covered in this Skill?' and 'When to use this skill' largely duplicate each other and the frontmatter description, and 'After editing this repository's XML sources, regenerate skills and verify the build' is repo-maintenance filler for a SQL skill.

Actionability

Concrete, executable commands are present ('Run `./mvnw compile` or `mvn compile`', 'Run `./mvnw clean verify` or `mvn clean verify`') alongside specific file paths and named deferral targets ('@311-frameworks-spring-jdbc', 'references/704-technologies-sql.md'), matching anchor 4. Not anchor 5 because no inline SQL example covers the common cases — everything executable lives in the reference — and workflow verbs like 'inspect current schema' remain high-level.

Workflow Clarity

The four-step sequence is clear and validation is explicitly present (step 4 'Execute appropriate build, migration, SQL validation, and test checks' plus the MANDATORY and VERIFY constraints), but there is no validate→fix→retry feedback loop — nothing says what to do when verification fails. The rubric's scoring note caps workflow_clarity at 3 for database-operation skills missing feedback loops, which overrides the otherwise anchor-4 fit.

Progressive Disclosure

The body is a concise, well-sectioned overview that delegates all detailed guidance and examples to a single one-level-deep reference, 'references/704-technologies-sql.md' (verified to exist, 184 lines, well-organized with its own table of contents), linked both in the Workflow step and a dedicated Reference section — a clear match for anchor 5's 'clear overview with well-signaled one-level-deep references'.

Specificity

The description lists nine concrete capability areas ("schema naming, relational table design, query readability, indexes, transactions, database security, migrations, testing, and monitoring"), which reads as a topic list rather than the action-verb coverage of the 5-anchor ("Extract text and tables from PDF files, fill forms, merge documents") — closer to anchor 4's 'several specific actions, minor gaps'. Per the judging guideline, the second-person phrase "Use when you need framework-agnostic SQL guidance" reduces this score by 1.

Completeness

It explicitly answers both what ("framework-agnostic SQL guidance — schema naming, relational table design, ... monitoring") and when ("This should trigger for requests such as Review SQL schema or migrations; ..."), with concrete trigger phrases — a clear match for anchor 5. Anchor 4 would require the 'when' to be less explicit, which it is not.

Trigger Term Quality

Trigger phrases are natural user requests ("Review SQL schema or migrations; Improve SQL query performance and readability; Design relational tables and indexes"), matching anchor 4's 'good keyword coverage; a few natural terms missing'. It falls short of anchor 5 because common synonyms and file extensions are absent (no '.sql', 'database queries', 'query tuning', 'DDL').

Distinctiveness Conflict Risk

The negative scoping "without choosing Spring Boot, Quarkus, or Micronaut" plus the framework deferrals makes the niche mostly distinct (anchor 4). Not anchor 5 because triggers like "Review SQL schema or migrations" still overlap with migration-tool (e.g., Flyway) and database-tuning skills, and "Part of Plinth Toolkit" adds no disambiguation.