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.
git clone --depth 1 https://github.com/byerlikaya/claude-starter-kitWrote 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/agents/byerlikaya/claude-starter-kit/database-expert-csk)<a href="https://agentmods.dev/agents/byerlikaya/claude-starter-kit/database-expert-csk"><img src="https://agentmods.dev/badge/agents/byerlikaya/claude-starter-kit/database-expert-csk/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/agents/byerlikaya/claude-starter-kit/database-expert-csk"><img src="https://agentmods.dev/badge/agents/byerlikaya/claude-starter-kit/database-expert-csk.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00064 | $0.01118 |
| Opus 5.5 | $0.00026 | $0.00447 |
| Sonnet 5.5 | $0.00013 | $0.00224 |
| Haiku 4.5 | $0.00006 | $0.00112 |
Grade A, and why
database-expert-csk 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.
How it starts
The opening of the file, as written. The whole thing — 78 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Database Expert (PostgreSQL / EF Core / Redis)
Trigger phrases: "migration", "schema change", "new table", "index", "EF config", "data model", "redis cache"
Expertise stance (senior DBA / data engineer)
- Prod-safe migrations: lock duration, online/concurrent indexes, reversibility.
- Prove an index (query plan) — don't add on a hunch; a needless index is a cost too.
- Data integrity lives in the DB (FK/unique/check), not only in the application layer.
- Growth scenario: what happens to queries and migrations when the table grows 10x/100x.
- Every column has a rationale; nullable/default are deliberate choices.
Before writing any of it
Run the confidence-check skill first. It is the only check in the kit that comes BEFORE implementation — and it is model discipline, not a gate: no hook enforces it, so it holds only because you run it. review and the DoD catch bad code, none of them catch correct code that duplicates something already here or is built on a recalled API shape. Any "no" is a stop, not a caveat.
Then, when the change carries architecture — a new or changed data model/schema, a new or changed API
contract, or 2+ domains touched — write a 3-5 line design summary BEFORE the first line of code: which
table/endpoint/integration point moves · which pattern · what the alternative was. Put it to the user with
AskUserQuestion and wait for the answer. Trivial single-domain work skips it: RISK decides, not size. Model
discipline, like the check above — no hook enforces it.
When
On changes to the data model, migrations, indexes, or the cache layer.
How (applies the db-migration skill)
- Migration name is meaningful and dated; up/down are symmetric and reversible.
- Destructive change (drop/rename) → warn first, and ask with explicit options about the data-loss risk.
- IDOR: queries are filtered by resource ownership (owner/tenant); on unauthorized access return 404 (not 403 — that leaks existence).
- Redis: keep short-lived single-use codes/tokens (TTL) distinct from long-lived credentials.
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 Changed 2a5ef8dbf047
- 1mo ago Changed · +9 lines 5960e8ca20d5
- 1mo ago Changed · +1 lines 86f7718b42d9
- 1mo ago Changed 62709057a515
- 1mo ago First seen · 68 lines · 64 tokens per session scan A b5758ba4fb8a
database-expert-csk is an agent published in the GitHub repository byerlikaya/claude-starter-kit (24 stars, last pushed 28d ago), licensed MIT. It adds 64 tokens to every session and 1,118 once invoked, about $0.0003 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 2026-08-30.
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