auditing-table-statistics
Audits optimizer table statistics for staleness, missing coverage, and data quality issues using SHOW STATISTICS. Use when diagnosing poor query performance, unexpected plan changes, or after bulk data changes to identify stale statistics requiring refresh via CREATE STATISTICS.
84
81%
Does it follow best practices?
Impact
Pending
No eval scenarios have been run
Passed
No known issues
Quality
Discovery
100%Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.
This is an excellent skill description that clearly defines a narrow, specific domain (optimizer statistics auditing), lists concrete actions and tools (SHOW STATISTICS, CREATE STATISTICS), and provides explicit trigger conditions covering multiple realistic scenarios. The description is concise, uses third person voice, and would be easily distinguishable from other database-related skills.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists multiple specific concrete actions: audits optimizer table statistics for staleness, missing coverage, and data quality issues using SHOW STATISTICS. Also mentions identifying stale statistics requiring refresh via CREATE STATISTICS. | 3 / 3 |
Completeness | Clearly answers both what ('Audits optimizer table statistics for staleness, missing coverage, and data quality issues using SHOW STATISTICS') and when ('Use when diagnosing poor query performance, unexpected plan changes, or after bulk data changes'). | 3 / 3 |
Trigger Term Quality | Includes strong natural trigger terms users would say: 'poor query performance', 'unexpected plan changes', 'bulk data changes', 'stale statistics', 'SHOW STATISTICS', 'CREATE STATISTICS', 'optimizer table statistics'. These cover the natural language a DBA or developer would use. | 3 / 3 |
Distinctiveness Conflict Risk | Highly distinctive niche focusing specifically on optimizer statistics auditing with SHOW STATISTICS and CREATE STATISTICS. Unlikely to conflict with general query tuning or database administration skills due to the precise scope. | 3 / 3 |
Total | 12 / 12 Passed |
Implementation
62%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
The skill provides highly actionable, executable SQL queries with excellent workflow structure and validation checkpoints. However, it is severely bloated—easily 2-3x longer than necessary—with extensive explanations of database concepts Claude already understands (what histograms are, what statistics do, basic optimizer behavior). The core diagnostic queries and workflows are strong, but they're buried in unnecessary educational content that should either be removed or moved to reference files.
Suggestions
Remove or drastically condense the 'Core Concepts' section—Claude understands optimizer statistics, histograms, and cardinality estimation. Keep only CockroachDB-specific behaviors (e.g., the 20% auto-collection threshold, multi-column stats requiring manual creation).
Move the 'Key Considerations' section to a reference file; most of it repeats information from earlier sections or explains concepts Claude already knows.
Consolidate the staleness indicator table, statistics lifecycle explanation, and threshold tuning into a single concise section or reference file rather than spreading across multiple sections.
Remove explanatory tables like 'What Are Table Statistics?' and 'Staleness Indicators'—these explain basic database concepts. Replace with a brief note on CockroachDB-specific defaults only.
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | Extremely verbose at ~400+ lines. Extensive explanations of concepts Claude already knows (what table statistics are, what histograms optimize, basic SQL concepts). The 'Core Concepts' section alone is unnecessary padding—Claude understands optimizer statistics. Tables explaining statistic types, staleness indicators, and collection schedules could be dramatically condensed. The 'Key Considerations' section rehashes information already covered earlier. | 1 / 3 |
Actionability | All queries are fully executable SQL with clear customization points marked by comments. The bash script for batch collection is copy-paste ready. Each query includes interpretation guidance and key column explanations. The troubleshooting table maps issues to concrete fixes with actual SQL commands. | 3 / 3 |
Workflow Clarity | Three well-defined workflows with numbered steps, explicit validation checkpoints (e.g., 'Verify refresh' step, 'Expected outcome' statements), and clear sequencing. The post-bulk-load workflow includes monitoring job progress before verification. Safety considerations include cancellation procedures and batch best practices with explicit resource monitoring. | 3 / 3 |
Progressive Disclosure | References to supplementary files (references/statistics-thresholds.md, references/create-statistics-examples.md) and related skills are well-signaled and one-level deep. However, the main SKILL.md contains far too much inline content that should be in reference files—the Core Concepts section, Key Considerations section, and detailed histogram/multi-column explanations would be better as referenced material. No bundle files were provided to verify references exist. | 2 / 3 |
Total | 9 / 12 Passed |
Validation
90%Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.
Validation — 10 / 11 Passed
Validation for skill structure
| Criteria | Description | Result |
|---|---|---|
skill_md_line_count | SKILL.md is long (701 lines); consider splitting into references/ and linking | Warning |
Total | 10 / 11 Passed | |
- Repository
- cockroachlabs/cockroachdb-skills
- Commit
84bc1e4
- Reviewed
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