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.
npx agentmods add rules/kok-o/koko-contextos-agents/databasegit clone --depth 1 https://github.com/kok-o/koko-contextos-agentsWhat 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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00024 | $0.01136 |
| Opus 5 | $0.00012 | $0.00568 |
| Sonnet 5 | $0.00005 | $0.00227 |
| Haiku 4.5 | $0.00002 | $0.00114 |
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 2d 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.
How it starts
The opening of the file, as written. The whole thing — 148 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Skill: database
Database
Overview
Relational database design, query optimization, migration safety, and ORM usage across PostgreSQL, Prisma, and Drizzle.
When to Use
Activate for tasks involving database schema design, migrations, indexing, relational models, ORM queries, transactions, or query performance tuning.
Rules & Patterns
Negative Constraints (What NOT to Do)
- NEVER do
SELECT *in production: Always select explicit columns required by the caller to minimize memory bandwidth and lock footprint. - NEVER run destructive migrations without backward compatibility: Always follow expand-and-contract (Phase 1: add new column as nullable; Phase 2: backfill; Phase 3: make non-nullable & remove old column).
- NEVER execute queries in loops (The N+1 Anti-Pattern): Always use batch loading (
inArray,DataLoader, or relationalinclude/JOIN). - NEVER leave foreign keys without indexes: In PostgreSQL/MySQL, child foreign key columns must always have an index to prevent table-level locking on cascade deletes.
- NEVER perform multi-entity writes without a database transaction: Any operation touching multiple records must use
prisma.$transactionordb.transaction.
Indexing & Performance Rules
- B-Tree Indexes: For high-cardinality filters (
status,user_id,created_at). - Composite Indexes: When querying multiple columns together (
WHERE organization_id = ? AND status = ?), order columns in index by equality first, range second. - Partial Indexes: For sparse boolean flags (
WHERE is_processed = false).
Code Examples
See EXAMPLES.md for complete anti-patterns and production code examples.
Validation Checklist
- All database queries select explicit required columns
- Foreign keys have matching indexes
- Multi-table writes wrapped in ACID transactions
- No N+1 queries in loops
Common Mistakes
- Missing pagination limits (
take / limit) on list endpoints. SeeTROUBLESHOOTING.md.
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.
- 2d ago First seen · 148 lines · 24 tokens per session scan A f054b03483d1
database is a cursor rule published in the GitHub repository kok-o/koko-contextos-agents (2 stars, last pushed 2d ago), licensed MIT. It adds 24 tokens to every session and 1,136 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 2026-08-31.
Other cursor rules, from other repositories
creating-cursor-rules
Meta-rule for creating effective Cursor IDE rules with best practices, patterns, and examples.
core
Read .apc/manifest.md first. If it contains placeholders and the user requests initialization, follow .apc/init.md. If the task concerns APC itself, edit prompt source without filling consumer placeholders. Otherwise follow .apc/workflow.md §0 or §1.
unity-performance
Cursor rule "unity-performance" from Common-ka/ai-agent-unity-rules, covering unity performance rules, update/fixedupdate/lateupdate, usage rules, object pooling (unityengine.pool) and addressables (not resources).
react-composition-patterns
React composition patterns for scalable component architecture including compound components, context providers, state management, boolean prop alternatives, render props vs children, and React 19 API changes. Use when refactoring components with many boolean props, building component libraries, designing flexible…
react-rerender-optimization
React re-render optimization patterns including memo, useMemo, useCallback, useState, useRef, and derived state. Use when components re-render too often, dealing with stale closures, dependency arrays, performance issues, or optimizing slow components.
index
This project uses Unity 6.2 (LTS 2025) with modern systems and architectural approaches.