database

database is a cursor rule for Cursor from gracefullight/docusaurus-plugins. It costs 0 tokens per session (368 once invoked), scanned A, a copy of database, MIT.

A set of rules for designing and maintaining SQL, NoSQL, and vector database schemas, including their structure, integrity, and performance needs.

In plain words
What is it for?
Use it to choose a database model, design schemas, define transactions and locking, plan indexes, document data rules, and estimate capacity.
Why use it?
It makes data models easier to reason about and exposes unsafe shortcuts, unclear consistency choices, and problems with concurrency or access patterns.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/.

Good fit Use it to choose a database model, design schemas, define transactions and locking, plan indexes, document data rules, and estimate capacity.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/gracefullight/docusaurus-plugins/database
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/gracefullight/docusaurus-plugins

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

README.md
[![agentmods](https://agentmods.dev/badge/rules/gracefullight/docusaurus-plugins/database/github.svg)](https://agentmods.dev/rules/gracefullight/docusaurus-plugins/database)
Your own site
<a href="https://agentmods.dev/rules/gracefullight/docusaurus-plugins/database"><img src="https://agentmods.dev/badge/rules/gracefullight/docusaurus-plugins/database/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

Your own site · 80×15
<a href="https://agentmods.dev/rules/gracefullight/docusaurus-plugins/database"><img src="https://agentmods.dev/badge/rules/gracefullight/docusaurus-plugins/database.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 368 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 86% copy Near-identical to another mod 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 $0.00000 $0.00368
Opus 5.5 $0.00000 $0.00147
Sonnet 5.5 $0.00000 $0.00074
Haiku 4.5 $0.00000 $0.00037

Measured 1mo ago against content hash 458386e74ecc, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

database 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 1mo 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.

Origin

This is a copy

86% identical to database — 10 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.cursor/rules/database.mdc · 26 lines

What it actually says

Database Standards

Core Rules

  1. Choose model first, engine second: workload, access pattern, consistency, and scale drive DB selection.
  2. For relational workloads, enforce at least 3NF by default. Break 3NF only with explicit performance justification.
  3. For distributed/non-relational workloads, model around aggregates and access paths; document BASE and consistency tradeoffs.
  4. Document ACID expectations for relational transactions. For distributed tradeoffs, document consistency compromises explicitly.
  5. Always document the three schema layers: external schema, conceptual schema, internal schema.
  6. Treat integrity as first-class: entity, domain, referential, and business-rule integrity must be explicit.
  7. Concurrency is never implicit: define transaction boundaries, locking strategy, and isolation level per critical flow.
  8. Data standards are mandatory: naming, definition, format, allowed values, and validation rules.
  9. Maintain living artifacts: glossary, schema decision log, and capacity estimation — update whenever the model changes.
  10. Proactively flag anti-patterns and insecure shortcuts instead of silently implementing them.
  11. Vector DBs are retrieval infrastructure, not source-of-truth databases. Store embeddings and metadata there; keep canonical documents elsewhere.
  12. Never treat vector search as a drop-in for lexical search. Default to hybrid retrieval when exact match or explainability matters.
  13. Embeddings are schema-like assets: version model, dimension, chunking, and preprocessing. Plan re-embedding migrations explicitly.
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. 1mo ago First seen · 26 lines · 0 tokens per session scan A 458386e74ecc

Subscribe to this mod's changes

database is a cursor rule published in the GitHub repository gracefullight/docusaurus-plugins (23 stars, last pushed 24d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 368 tokens. A static security scan graded it A with 0 findings. It is 86% identical to database, differing in 10 lines, and is treated as a copy.