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creating-claude-rules

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Use when creating or fixing .claude/rules/ files - provides correct paths frontmatter (not globs), glob patterns, and avoids Cursor-specific fields like alwaysApply

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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 (globs instead of paths)
  • Migrating Cursor rules to Claude format
  • Organizing project-specific conventions

Quick Reference

FieldClaudeCursor
Path patternspathsglobs
Always applyOmit pathsalwaysApply: true
DescriptionNot documenteddescription

Frontmatter

Path-Scoped Rules

---
paths:
  - 'src/api/**/*.ts'
  - 'tests/**/*.test.ts'
---

Or single pattern:

---
paths: src/**/*.{ts,tsx}
---

Global Rules

Omit frontmatter entirely - applies to all files:

# TypeScript Conventions

Use .js extensions in imports.

Common Mistakes

# ❌ WRONG - globs is Cursor format
---
globs:
  - '**/*.ts'
---
# ✅ CORRECT - Claude uses paths
---
paths:
  - '**/*.ts'
---
# ❌ WRONG - alwaysApply is Cursor-only
---
alwaysApply: true
---
# ✅ CORRECT - just omit paths for global rules
# (no frontmatter needed)
# ❌ 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

PatternMatches
**/*.tsAll .ts files anywhere
src/**/*Everything under src/
*.mdMarkdown 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/