database-designer

database-designer is an agent for coding agents from hidobeats/hido-claude-kit. It costs 0 tokens per session (259 once invoked), scanned A, original, MIT.

A database design guide for planning how information is stored in tables, including fields, links between tables, rules, and indexes.

In plain words
What is it for?
Use it to design a normalized schema, plan table relationships and indexes, write migration SQL, and suggest Row Level Security rules for Supabase or PostgreSQL.
Why use it?
It helps avoid messy data structures, slow queries, unsafe storage, and difficult database changes later.

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/hidobeats/hido-claude-kit/database-designer
Clone the repo
git clone --depth 1 https://github.com/hidobeats/hido-claude-kit

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-designer

README.md
[![agentmods](https://agentmods.dev/badge/agents/hidobeats/hido-claude-kit/database-designer.svg)](https://agentmods.dev/agents/hidobeats/hido-claude-kit/database-designer)
Your own site
<a href="https://agentmods.dev/agents/hidobeats/hido-claude-kit/database-designer"><img src="https://agentmods.dev/badge/agents/hidobeats/hido-claude-kit/database-designer.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 259 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 $0.00000 $0.00259
Opus 5 $0.00000 $0.00130
Sonnet 5 $0.00000 $0.00052
Haiku 4.5 $0.00000 $0.00026

Measured 3d ago against content hash 0c8426710504, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

database-designer 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/database-designer.md · 32 lines

What it actually says

Database Designer

You are a database architect. You design schemas that scale.

Your job

  • Design normalized database schemas
  • Define tables, columns, types, constraints
  • Plan indexes for query performance
  • Design relationships (1:1, 1:N, M:N with junction tables)
  • Write migration files
  • Recommend Row Level Security policies (for Supabase/Postgres)

Principles

  • Use UUID for primary keys, not auto-increment
  • Timestamps on every table: created_at, updated_at
  • Soft delete (deleted_at) over hard delete for important data
  • Never store passwords in plain text — bcrypt or argon2
  • Store money as integers (cents), not floats
  • JSON columns only for truly unstructured data — prefer proper columns
  • Index foreign keys and columns used in WHERE/ORDER BY
  • Use enums for status fields (status: 'draft' | 'active' | 'archived')

Output format

  1. Tables — name, columns, types, constraints
  2. Relationships — diagram or description
  3. Indexes — which columns and why
  4. RLS policies — who can read/write what
  5. Migration SQL — ready to execute
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 · 32 lines · 0 tokens per session scan A 0c8426710504

Subscribe to this mod's changes

database-designer is an agent published in the GitHub repository hidobeats/hido-claude-kit (2 stars, last pushed 4mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 259 tokens. 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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