database-design

database-design is a cursor rule for Cursor from MN-Lizard-Team/aiyu-multi-agent. It costs 20 tokens per session (360 once invoked), scanned A, original, Apache-2.0.

Guidance for designing databases, including choosing a database and ORM, structuring schemas, defining relationships, adding indexes, optimizing queries, and handling migrations. An ORM is a programming layer that maps application objects to database records.

In plain words
What is it for?
Use it when selecting PostgreSQL, SQLite, or another database, designing tables, planning indexes, choosing an ORM, improving queries, or changing a schema safely.
Why use it?
It helps avoid poor schema choices, slow queries, unsafe schema changes, and database tools that do not fit the deployment environment.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/. Also seen: mentions Cursor.

Good fit Use it when selecting PostgreSQL, SQLite, or another database, designing tables, planning indexes, choosing an ORM, improving queries, or changing a schema safely.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/mn-lizard-team/aiyu-multi-agent/database-design
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/MN-Lizard-Team/aiyu-multi-agent

Made for: Cursor.

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-design

README.md
[![agentmods](https://agentmods.dev/badge/rules/mn-lizard-team/aiyu-multi-agent/database-design.svg)](https://agentmods.dev/rules/mn-lizard-team/aiyu-multi-agent/database-design)
Your own site
<a href="https://agentmods.dev/rules/mn-lizard-team/aiyu-multi-agent/database-design"><img src="https://agentmods.dev/badge/rules/mn-lizard-team/aiyu-multi-agent/database-design.svg" alt="Measured on agentmods" height="20"></a>
Per session 20 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 360 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 $0.00020 $0.00360
Opus 5 $0.00010 $0.00180
Sonnet 5 $0.00004 $0.00072
Haiku 4.5 $0.00002 $0.00036

Measured 4d ago against content hash 9397c240b911, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

database-design 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.

.cursor/rules/skills/database-design.mdc · 56 lines

What it actually says

Skill: database-design

Cursor Agent-Requested Rule — applied when AI determines relevance.


Database Design

Learn to THINK, not copy SQL patterns.

🎯 Selective Reading Rule

Read ONLY files relevant to the request! Check the content map, find what you need.

File Description When to Read
database-selection.md PostgreSQL vs Neon vs Turso vs SQLite Choosing database
orm-selection.md Drizzle vs Prisma vs Kysely Choosing ORM
schema-design.md Normalization, PKs, relationships Designing schema
indexing.md Index types, composite indexes Performance tuning
optimization.md N+1, EXPLAIN ANALYZE Query optimization
migrations.md Safe migrations, serverless DBs Schema changes

⚠️ Core Principle

  • ASK user for database preferences when unclear
  • Choose database/ORM based on CONTEXT
  • Don't default to PostgreSQL for everything

Decision Checklist

Before designing schema:

  • Asked user about database preference?
  • Chosen database for THIS context?
  • Considered deployment environment?
  • Planned index strategy?
  • Defined relationship types?

Anti-Patterns

❌ Default to PostgreSQL for simple apps (SQLite may suffice) ❌ Skip indexing ❌ Use SELECT * in production ❌ Store JSON when structured data is better ❌ Ignore N+1 queries

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 · 56 lines · 20 tokens per session scan A 9397c240b911

Subscribe to this mod's changes

database-design is a cursor rule published in the GitHub repository MN-Lizard-Team/aiyu-multi-agent (7 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 20 tokens to every session and 360 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 2026-09-03.