Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add HoangNguyen0403/agent-skills-standard --skill database-query-performancegit clone --depth 1 https://github.com/HoangNguyen0403/agent-skills-standardWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/hoangnguyen0403/agent-skills-standard/database-query-performance)<a href="https://agentmods.dev/skills/hoangnguyen0403/agent-skills-standard/database-query-performance"><img src="https://agentmods.dev/badge/skills/hoangnguyen0403/agent-skills-standard/database-query-performance/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/hoangnguyen0403/agent-skills-standard/database-query-performance"><img src="https://agentmods.dev/badge/skills/hoangnguyen0403/agent-skills-standard/database-query-performance.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00042 | $0.00321 |
| Opus 5.5 | $0.00017 | $0.00128 |
| Sonnet 5.5 | $0.00008 | $0.00064 |
| Haiku 4.5 | $0.00004 | $0.00032 |
Grade A, and why
database-query-performance scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
Database Query Performance
Priority: P0 (CRITICAL)
Slow query work starts with the query shape and evidence, not with random index creation.
Rules
- Capture the exact query, parameters, and access path.
- Run explain or equivalent plan inspection before adding indexes.
- Match indexes to filter, join, sort, and coverage needs.
- Fix N+1 at the query pattern or loading strategy, not by caching first.
Verify
- Explain plan was reviewed.
- Proposed index maps to a named query path.
- Write cost of the index is acceptable.
- Pagination or batch loading avoids deep scans or N+1 loops.
Anti-Patterns
- No blind indexes: every index needs a query owner.
- No cache-first latency fix: fix query shape before hiding it.
- No ORM opacity: inspect generated SQL when the ORM is involved.
References
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago First seen · 47 lines · 42 tokens per session scan A 2b036001cef9
database-query-performance is a skill published in the GitHub repository HoangNguyen0403/agent-skills-standard (582 stars, last pushed today), licensed MIT. It adds 42 tokens to every session and 321 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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prompt-2-data
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database-design
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Vector Databases
Guides retrieval-store design, indexing, and query behavior for embedding-backed systems without confusing storage with application truth.