database-expert

database-expert is an agent for Claude Code from GoogilyBoogily/googilyboogily-claude-power-tools. It costs 40 tokens per session (737 once invoked), scanned A, original, MIT.

A general guide for working with databases such as PostgreSQL, MongoDB, MySQL, and SQLite. It helps decide when a database problem should be handed to a more specialised guide.

In plain words
What is it for?
Use it for database structure, queries, connections, migrations, transactions, and problems involving more than one database system.
Why use it?
It reduces the guesswork when a project uses different databases, database libraries, or shared database patterns. It also helps avoid sending engine-specific problems to the wrong place.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: model in frontmatter.

Part of the database-agents plugin — 4 agents shipped together

Good fit Use it for database structure, queries, connections, migrations, transactions, and problems involving more than one database system.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/googilyboogily/googilyboogily-claude-power-tools/database-expert
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.

Clone the repo
git clone --depth 1 https://github.com/GoogilyBoogily/googilyboogily-claude-power-tools

Made for: Claude Code.

Or install database-agents, the plugin that ships this one along with the rest of its 4 agents.

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 database-expert

README.md
[![agentmods](https://agentmods.dev/badge/agents/googilyboogily/googilyboogily-claude-power-tools/database-expert/github.svg)](https://agentmods.dev/agents/googilyboogily/googilyboogily-claude-power-tools/database-expert)
Your own site
<a href="https://agentmods.dev/agents/googilyboogily/googilyboogily-claude-power-tools/database-expert"><img src="https://agentmods.dev/badge/agents/googilyboogily/googilyboogily-claude-power-tools/database-expert/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.

agentmods 80×15 button for database-expert

Your own site · 80×15
<a href="https://agentmods.dev/agents/googilyboogily/googilyboogily-claude-power-tools/database-expert"><img src="https://agentmods.dev/badge/agents/googilyboogily/googilyboogily-claude-power-tools/database-expert.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 40 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 737 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00040 $0.00737
Opus 5 $0.00020 $0.00368
Sonnet 5 $0.00008 $0.00147
Haiku 4.5 $0.00004 $0.00074

Measured 12d ago against content hash 09d83cdd518c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

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 12d 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.

plugins/database-agents/agents/database-expert.md · 65 lines

How it starts

The opening of the file, as written. The whole thing — 65 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Database Expert

Cross-database generalist. Route to specialists when the problem is DB-engine-specific.

Step 0: Route or Stay

Evaluate FIRST. If any condition matches, STOP and hand off:

Condition Route to Examples
PostgreSQL-specific (MVCC, vacuum, pg_stat, partitioning, GIN/GiST indexes) postgres-expert vacuum tuning, pg_locks, BRIN indexes
MongoDB-specific (aggregation pipelines, sharding, replica sets, document design) mongodb-expert $lookup optimization, shard key selection
Query plan analysis, slow query triage, index recommendations optimizer EXPLAIN plans, missing indexes, N+1 detection
Next.js API routes with DB calls nextjs-expert Server Actions + Prisma
General architecture decisions involving DB choice suggest user run /quality-agents:architect-reviewer "Should I use Postgres or Mongo?"

Stay here when the problem spans multiple databases, involves ORM wiring, connection config, migration strategy, or cross-DB patterns.

Step 1: Detect Environment

Scan the project to determine what is in play:

  • Connection strings: postgresql://, mysql://, mongodb://, sqlite:///
  • Config files: postgresql.conf, my.cnf, mongod.conf
  • ORM/driver deps: prisma, typeorm, sequelize, mongoose, drizzle, knex
  • Default ports: 5432 (Postgres), 3306 (MySQL), 27017 (MongoDB)

Step 2: Cross-DB Patterns

These apply regardless of engine:

Connection Management

  • Always use connection pooling. Size pool to (cores * 2) + spindles as a starting point.
  • Postgres uses ~9MB/connection (pooling is critical); MySQL uses ~256KB/thread (more forgiving).
  • Ensure connections are released in error paths (finally blocks, middleware cleanup).

N+1 Prevention

  • ORM eager loading: Prisma include, TypeORM eager: true / relations, Mongoose populate.
  • Prefer JOINs or batch queries over loops issuing single-row SELECTs.

Migration Safety

  • Always test migrations against production-sized data before deploying.
  • Use CREATE INDEX CONCURRENTLY (Postgres) or equivalent to avoid table locks.
  • Provide a rollback path for every migration.

Read the full file on GitHub · 65 lines

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. 12d ago First seen · 65 lines · 40 tokens per session scan A 09d83cdd518c

Subscribe to this mod's changes

database-expert is an agent published in the GitHub repository GoogilyBoogily/googilyboogily-claude-power-tools (2 stars, last pushed 4mo ago), licensed MIT. It adds 40 tokens to every session and 737 once invoked, about $0.0002 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.

Related

Other agents, from other repositories

MS-SQL Database Administrator

Work with Microsoft SQL Server databases using the MS SQL extension.

github/awesome-copilot · 18 tokens

core-data-auditor

Use this agent when the user mentions Core Data review, schema migration, production crashes, or data safety checking. Automatically scans Core Data code for the 5 most critical safety violations - schema migration risks, thread-confinement errors, N+1 query patterns, production data loss risks, and performance issues…

CharlesWiltgen/Axiom · 261 tokens

lens

Turns raw data into actionable decisions — dashboards, metric definitions, SQL analytics, funnel and cohort analysis across BI platforms. Use when designing a dashboard, defining KPIs, or running funnel analysis. Trigger with "design a dashboard", "analyze our funnel".

jeremylongshore/tons-of-skills-marketplace · 53 tokens

ecto-schema-designer

Ecto schema architect - designs migrations, data models, and query patterns. Use proactively when planning database structure for new features.

oliver-kriska/claude-elixir-phoenix · 30 tokens

django-migrations-specialist

Database specialist for Django, runs in the "database" extra phase after development. Finalizes model field types and Meta indexes/constraints, runs makemigrations, reviews generated SQL with sqlmigrate, runs migrate, verifies with migrate --check. Do NOT use for: application logic (django-architect), tests…

AratKruglik/claude-sdlc · 85 tokens

database-architect

Use this agent for database design and change work: schema design, indexing strategy, query optimization, migration safety, and engine selection. Trigger on "design a schema for", "this query is slow", "is this migration safe", "add an index", "Postgres or Mongo for this", or N+1 complaints. Returns schema/DDL with…

aayushostwal/nexus · 96 tokens