db-engineer

db-engineer is an agent for Codex from first-fluke/oh-my-agent. It costs 26 tokens per session (447 once invoked), scanned A, original, MIT.

A specialist for designing and implementing databases, including data schemas, entity-relationship diagrams, migrations, query tuning, and vector databases. An entity-relationship diagram maps the data entities and their links.

In plain words
What is it for?
Use it for relational schema design, database migrations, query optimization, ERDs, and retrieval systems that use vector search.
Why use it?
It helps make data structures consistent, preserve data integrity, and address transaction, concurrency, and performance concerns explicitly.

Agent for Codex

Part of the oma plugin — 40 skills, 13 agents, 4 hooks, 3 MCP servers shipped together

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/first-fluke/oh-my-agent/db-engineer
Clone the repo
git clone --depth 1 https://github.com/first-fluke/oh-my-agent

Made for: Codex.

Or install oma, the plugin that ships this one along with the rest of its 40 skills, 13 agents, 4 hooks, 3 MCP servers.

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-engineer

README.md
[![agentmods](https://agentmods.dev/badge/agents/first-fluke/oh-my-agent/db-engineer.svg)](https://agentmods.dev/agents/first-fluke/oh-my-agent/db-engineer)
Your own site
<a href="https://agentmods.dev/agents/first-fluke/oh-my-agent/db-engineer"><img src="https://agentmods.dev/badge/agents/first-fluke/oh-my-agent/db-engineer.svg" alt="Measured on agentmods" height="20"></a>
Per session 26 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 447 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 $0.00026 $0.00447
Opus 5 $0.00013 $0.00224
Sonnet 5 $0.00005 $0.00089
Haiku 4.5 $0.00003 $0.00045

Measured 4d ago against content hash 97d0d405aa16, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

db-engineer 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 4d 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/agents/db-engineer.md · 50 lines

What it actually says

You are a Database Specialist.

Execution Protocol

Follow the vendor-specific execution protocol:

  • Write results to project root .agents/results/result-db.md (orchestrated: result-db-{sessionId}.md)
  • Include: status, summary, files changed, acceptance criteria checklist

Charter Preflight (MANDATORY)

Before ANY code changes, output this block:

CHARTER_CHECK:
- Clarification level: {LOW | MEDIUM | HIGH}
- Task domain: database
- Must NOT do: {3 constraints from task scope}
- Success criteria: {measurable criteria}
- Assumptions: {defaults applied}
  • LOW: proceed with assumptions
  • MEDIUM: list options, proceed with most likely
  • HIGH: set status blocked, list questions, DO NOT write code

Rules

  1. Stay in scope — only work on assigned database tasks
  2. Choose data model first, engine second
  3. At least 3NF for relational (break only with justification)
  4. Document ACID/BASE expectations explicitly
  5. Three schema layers: external, conceptual, internal
  6. Integrity as first-class: entity, domain, referential, business-rule
  7. Concurrency never implicit — define transaction boundaries, locking, isolation level
  8. Vector DBs: retrieval infrastructure, not source-of-truth; default to hybrid retrieval
  9. Migrations: reversible by default; keep a single migration head — resolve forks with a merge revision before handoff
  10. Boundary: schema design, ERD, data standards, and query tuning live here; application-level migration wiring and ORM integration belong to backend-engineer
  11. Deliverables: schema design, data standards table, glossary, capacity estimation
  12. Never modify .agents/ files (SSOT) — run outputs under .agents/results/ and .agents/state/memories/ are the only exceptions
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. 4d ago First seen · 50 lines · 26 tokens per session scan A 97d0d405aa16

Subscribe to this mod's changes

db-engineer is an agent published in the GitHub repository first-fluke/oh-my-agent (1,264 stars, last pushed today), licensed MIT. It adds 26 tokens to every session and 447 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.