craft-db

craft-db is a skill for Claude Code from gul-labs/craftsman-marketplace. It costs 118 tokens per session (2,294 once invoked), scanned A, original, MIT.

A set of guidelines for database work, including table design, migrations, queries, indexes, and separating data between customers or organisations.

In plain words
What is it for?
Use it when designing or changing tables, writing migrations or queries, adding indexes, or enforcing customer-specific data access.
Why use it?
It helps developers extend the project’s existing database patterns and avoid unsafe queries or conflicting schema changes.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the craftsman plugin — 12 skills shipped together

Good fit Use it when designing or changing tables, writing migrations or queries, adding indexes, or enforcing customer-specific data access.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/gul-labs/craftsman-marketplace/craft-db
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.

Any agent
npx skills add gul-labs/craftsman-marketplace --skill craft-db
Clone the repo
git clone --depth 1 https://github.com/gul-labs/craftsman-marketplace

Made for: Claude Code.

Or install craftsman, the plugin that ships this one along with the rest of its 12 skills.

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 craft-db

README.md
[![agentmods](https://agentmods.dev/badge/skills/gul-labs/craftsman-marketplace/craft-db/github.svg)](https://agentmods.dev/skills/gul-labs/craftsman-marketplace/craft-db)
Your own site
<a href="https://agentmods.dev/skills/gul-labs/craftsman-marketplace/craft-db"><img src="https://agentmods.dev/badge/skills/gul-labs/craftsman-marketplace/craft-db/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 craft-db

Your own site · 80×15
<a href="https://agentmods.dev/skills/gul-labs/craftsman-marketplace/craft-db"><img src="https://agentmods.dev/badge/skills/gul-labs/craftsman-marketplace/craft-db.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 118 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,294 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 $0.00118 $0.02294
Opus 5 $0.00059 $0.01147
Sonnet 5 $0.00024 $0.00459
Haiku 4.5 $0.00012 $0.00229

Measured 12d ago against content hash 8602e96fe6be, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

craft-db 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/craftsman/skills/craft-db/SKILL.md · 158 lines

How it starts

The opening of the file, as written. The whole thing — 158 lines — stays where its author put it; the contents beside it link to each section on GitHub.

DB Craft

This skill encodes one engineer's standard for database work, applied the same way across every repo. The method and opinions live here; the specifics (which ORM, which dialect, which migration tool, what the tenant-scope helper is called) live in the target repo — always discover them first, never assume or hardcode.

Operating principle — discover before you build

Different repos are at different points in their DB evolution. Before touching anything, spend a few minutes mapping what already exists so you extend rather than duplicate or fight the grain:

  • package.json / lockfile → is drizzle-orm, prisma, knex, pg, mysql2, or similar already present?
  • Existing migration directory (e.g. drizzle/, prisma/migrations/, db/migrations/) → what conventions are already established (naming, timestamps, reversibility)?
  • Schema files → column naming style (camelCase vs snake_case), timestamp columns (createdAt / created_at), soft-delete column name and type, how tenant id is stored and named.
  • Query helpers → is there a shared conditions/helpers file that enforces tenant scoping and soft-delete filters? Read it before writing any query.
  • Dialect → Postgres, MySQL, SQLite? Some patterns (advisory locks, RETURNING, expression indexes) are dialect-specific.

State what you found, then propose the smallest set of changes that achieves the goal.

The data layers (work in this order)

  1. Schema design — model the domain correctly before writing a line of migration code. Choose the right types, enforce NOT NULL where the domain demands it, express relationships as real foreign keys, and name columns consistently with the existing schema. See references/schema.md.

  2. Migrations — translate the schema design into a forward-only migration, reviewed before it ever runs. Prefer reversible migrations where the cost is low (drop → add back); know when forward-only is the honest choice. See references/migrations.md.

Read the full file on GitHub · 158 lines

Files

What ships with it

7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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 · 158 lines · 118 tokens per session scan A 8602e96fe6be

Subscribe to this mod's changes

craft-db is a skill published in the GitHub repository gul-labs/craftsman-marketplace (1 stars, last pushed today), licensed MIT. It adds 118 tokens to every session and 2,294 once invoked, about $0.0006 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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