Rules
7. Rules (Project Rules / Instructions)¶
Rules provide persistent context — coding standards, architecture conventions, and project-specific guidance.
Universal Format: RULE.md¶
---
description: "TypeScript coding standards for this project"
globs: "src/**/*.{ts,tsx}"
alwaysApply: false
---
# TypeScript Standards
- Use strict mode
- Prefer `const` over `let`
- Use early returns
- Named exports only
- Co-locate tests as `*.test.ts`
Frontmatter Fields¶
| Field | Type | Required | Description |
|---|---|---|---|
description |
string |
Yes | Purpose of rule. Used for agent auto-selection. |
globs |
string |
No | File patterns for auto-attachment. |
alwaysApply |
boolean |
No | Always include in context. Default: false. |
Platform Mapping¶
| Platform | Native Format | Migration |
|---|---|---|
| Claude Code | CLAUDE.md (freeform) |
Copy content into CLAUDE.md |
| Cursor | .mdc / RULE.md in .cursor/rules/ |
Copy to .cursor/rules/ |
| Codex | AGENTS.md |
Copy into AGENTS.md sections |
| Universal | AGENTS.md (project root) |
Direct (supported everywhere) |
AGENTS.md as Universal Fallback¶
AGENTS.md at the project root is the most portable instruction format — supported by Claude Code, Cursor, Codex, Copilot, Gemini CLI, Jules, Amp, and others. Every universal package SHOULD include an AGENTS.md for maximum compatibility.