Creating Claude Rules
Overview
Rules in .claude/rules/ are modular instructions scoped to specific files via glob patterns. They load automatically with same priority as CLAUDE.md.
When to Use
- Creating new rules in
.claude/rules/ - Fixing rules that use wrong frontmatter (
globsinstead ofpaths) - Migrating Cursor rules to Claude format
- Organizing project-specific conventions
Quick Reference
| Field | Claude | Cursor |
|---|---|---|
| Path patterns | paths | globs |
| Always apply | Omit paths | alwaysApply: true |
| Description | Not documented | description |
Frontmatter
Path-Scoped Rules
yaml--- paths: - 'src/api/**/*.ts' - 'tests/**/*.test.ts' ---
Or single pattern:
yaml--- paths: src/**/*.{ts,tsx} ---
Global Rules
Omit frontmatter entirely - applies to all files:
markdown# TypeScript Conventions Use .js extensions in imports.
Common Mistakes
yaml# ❌ WRONG - globs is Cursor format --- globs: - '**/*.ts' --- # ✅ CORRECT - Claude uses paths --- paths: - '**/*.ts' ---
yaml# ❌ WRONG - alwaysApply is Cursor-only --- alwaysApply: true --- # ✅ CORRECT - just omit paths for global rules # (no frontmatter needed)
yaml# ❌ WRONG - unquoted patterns --- paths: - **/*.ts --- # ✅ CORRECT - quote glob patterns --- paths: - "**/*.ts" ---
Directory Structure
.claude/rules/ ├── testing.md # Path-scoped or global ├── typescript.md └── frontend/ # Subdirectories supported └── react.md
Files discovered recursively. Use subdirectories to organize.
Glob Patterns
| Pattern | Matches |
|---|---|
**/*.ts | All .ts files anywhere |
src/**/* | Everything under src/ |
*.md | Markdown in root only |
**/*.{ts,tsx} | .ts and .tsx files |
{src,lib}/**/*.ts | .ts in src/ or lib/ |
Reference
https://code.claude.com/docs/en/memory#modular-rules-with-claude/rules/
