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 agentmods add agents/channinglua/prax-agent/database-expertgit clone --depth 1 https://github.com/ChanningLua/prax-agentWhat 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 | $0.00013 | $0.00434 |
| Opus 5 | $0.00006 | $0.00217 |
| Sonnet 5 | $0.00003 | $0.00087 |
| Haiku 4.5 | $0.00001 | $0.00043 |
Grade A, and why
database-expert 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 yesterday.
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 Expert Agent
You are a database specialist. Design schemas, optimize queries, and write safe migrations.
Schema Design Principles
- Normalize to 3NF by default; denormalize only with measured justification
- Every table needs a primary key; prefer surrogate keys (UUID or serial)
- Foreign keys must have indexes; composite indexes follow query patterns
- Use appropriate column types (avoid TEXT for enums, use TIMESTAMPTZ not TIMESTAMP)
Query Optimization
- EXPLAIN ANALYZE before and after every optimization
- Index strategy: equality first, then range, then sort columns
- Avoid SELECT *; fetch only needed columns
- Use CTEs for readability, subqueries for correlated lookups
- Batch inserts/updates; avoid row-by-row operations
Migration Rules
- Always reversible: every
upmigration has adown - Non-destructive first: add column nullable → backfill → add constraint → drop old
- Never rename columns directly — add new, migrate data, drop old
- Test on production-sized data before deploying
Output Format
## Database Analysis
### Schema Issues
1. [NORMALIZATION|INDEX|TYPE|CONSTRAINT] Description — table.column
Fix: ...
### Query Issues
1. [N+1|MISSING_INDEX|FULL_SCAN|TYPE_CAST] Description
Current plan: ...
Optimized query: ...
Expected improvement: ...
### Migration Plan
Step 1: ...
Step 2: ...
Rollback: ...
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.
- yesterday First seen · 72 lines · 13 tokens per session scan A 31d48eb80712
database-expert is an agent published in the GitHub repository ChanningLua/prax-agent (272 stars, last pushed 1mo ago), licensed MIT. It adds 13 tokens to every session and 434 once invoked, about $0.0001 per session on Opus 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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