cursor-rules

A set of instructions for adding or changing Cursor editor rules, which are project-specific guidance files for an AI coding assistant.

In plain words
What is it for?
It is for creating kebab-case `.mdc` files under `.cursor/rules/` with descriptions, file patterns, application settings, guidance, and examples.
Why use it?
It prevents rules from being stored in the wrong place or with an invalid name or format.

Cursor rule for Cursor

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 rules/usekaneo/kaneo/cursor-rules
Clone the repo
git clone --depth 1 https://github.com/usekaneo/kaneo

Made for: Cursor.

Per session 10 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 317 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 $0.00010 $0.00317
Opus 5 $0.00005 $0.00159
Sonnet 5 $0.00002 $0.00063
Haiku 4.5 $0.00001 $0.00032

Measured 2d ago against content hash b7c93170746f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

cursor-rules 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.

Origin

Copies of this mod

2 near-identical copies found in the catalogue:

.cursor/rules/cursor-rules.mdc · 66 lines

What it actually says

Cursor Rules Location

How to add new cursor rules to the project

  1. Always place rule files in PROJECT_ROOT/.cursor/rules/:

    .cursor/rules/
    ├── your-rule-name.mdc
    ├── another-rule.mdc
    └── ...
    
  2. Follow the naming convention:

    • Use kebab-case for filenames
    • Always use .mdc extension
    • Make names descriptive of the rule's purpose
  3. Directory structure:

    PROJECT_ROOT/
    ├── .cursor/
    │   └── rules/
    │       ├── your-rule-name.mdc
    │       └── ...
    └── ...
    
  4. Never place rule files:

    • In the project root
    • In subdirectories outside .cursor/rules
    • In any other location
  5. Cursor rules have the following structure:

---
description: Short description of the rule's purpose
globs: optional/path/pattern/**/* 
alwaysApply: false
---
# Rule Title

Main content explaining the rule with markdown formatting.

1. Step-by-step instructions
2. Code examples
3. Guidelines

Example:
```typescript
// Good example
function goodExample() {
  // Implementation following guidelines
}

// Bad example
function badExample() {
  // Implementation not following guidelines
}
```
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. 2d ago First seen · 66 lines · 10 tokens per session scan A b7c93170746f

Subscribe to this mod's changes

cursor-rules is a cursor rule published in the GitHub repository usekaneo/kaneo (8,904 stars, last pushed yesterday), licensed MIT. It adds 10 tokens to every session and 317 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 2026-08-30.