db-check

db-check is an agent for coding agents from cveralyon/axel-setup. It costs 13 tokens per session (157 once invoked), scanned A, original, MIT.

A read-only checker for the health of a Rails database, including migrations, schema, indexes, and common query risks.

In plain words
What is it for?
Use it to check unfinished migrations, compare the schema with migrations, find missing indexes, and spot likely N+1 queries.
Why use it?
It finds database problems before they cause failed deployments, slow queries, or unnecessary database work.

Agent

Install

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.

agentmods
npx agentmods add agents/cveralyon/axel-setup/db-check
Clone the repo
git clone --depth 1 https://github.com/cveralyon/axel-setup

Wrote 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.

agentmods badge for db-check

README.md
[![agentmods](https://agentmods.dev/badge/agents/cveralyon/axel-setup/db-check.svg)](https://agentmods.dev/agents/cveralyon/axel-setup/db-check)
Your own site
<a href="https://agentmods.dev/agents/cveralyon/axel-setup/db-check"><img src="https://agentmods.dev/badge/agents/cveralyon/axel-setup/db-check.svg" alt="Measured on agentmods" height="20"></a>
Per session 13 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 157 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00013 $0.00157
Opus 5 $0.00006 $0.00078
Sonnet 5 $0.00003 $0.00031
Haiku 4.5 $0.00001 $0.00016

Measured 3d ago against content hash 1df78f6d2fc0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

db-check 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 3d 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.

agents/db-check.md · 15 lines

What it actually says

Check database health for your Rails API.

  1. Pending migrations: RAILS_ENV=development rails db:migrate:status
  2. Schema consistency: compare db/schema.rb with actual migrations
  3. Missing indexes: scan models for belongs_to/has_many without corresponding indexes
  4. N+1 risks: grep for .each loops calling associations without includes
  5. Large tables without indexes: check for columns used in where/order without indexes

Report findings grouped by priority. Never run destructive commands — read-only analysis only.

Changes

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.

  1. 3d ago First seen · 15 lines · 13 tokens per session scan A 1df78f6d2fc0

Subscribe to this mod's changes

db-check is an agent published in the GitHub repository cveralyon/axel-setup (4 stars, last pushed 1mo ago), licensed MIT. It adds 13 tokens to every session and 157 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 2026-08-31.

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