SUMMARY
Claude Code (CLI) uses markdown configuration while Cursor (IDE) uses mdc. They differ on 5 of 11 compared features. Both tools provide AI-assisted development but take different approaches to project configuration.
FEATURE COMPARISON
| Feature | Claude Code | Cursor |
|---|---|---|
| Config format | markdown | mdc |
| Hierarchy support | ✓ | ✓ |
| Global config | ✓ | ✓ |
| Project config | ✓ | ✓ |
| Subdirectory scoping | ✓ | ✓ |
| File inclusion / imports | ✓ | ✗ |
| Ignore file | .claudeignore | .cursorignore |
| IDE integration | CLI | ✓ |
| Schema / structure | Free-form (Markdown) | Hybrid (MDC frontmatter + Markdown) |
| Git committed | ✓ | ✓ |
| Encoding | UTF-8 | UTF-8 |
FILE MAPPING
| Purpose | Claude Code | Cursor |
|---|---|---|
| Project instructions | CLAUDE.md | .cursor/rules/*.mdc |
| Ignore patterns | .claudeignore | .cursorignore |
| Project rules | .claude/rules/*.md | .cursor/rules/*.mdc |
SIDE-BY-SIDE CODE SAMPLES
# Project Name
> TypeScript + React monorepo. Deployed on Vercel.
## Code Style
- TypeScript strict mode — no `any`, no `ts-ignore`
- Named exports only (no default exports)
- Prefer functional patterns: map/filter/reduce over for-loops
- Error handling: use Result<T, E> from `src/lib/result.ts`
## Architecture
- `src/routes/` — Route handlers (thin layer, delegates to services)
- `src/services/` — Business logic, one file per domain entity
- `src/db/` — Drizzle ORM schema and query helpers
- `src/lib/` — Shared utilities (logger, result type, validation)
## Commands
```bash
pnpm install # Install dependencies
pnpm dev # Start dev server (port 3000)
pnpm test # Run Vitest suite
pnpm test:e2e # Run Playwright tests
pnpm lint # ESLint + Prettier check
pnpm db:migrate # Run pending Drizzle migrations
```
## Git Conventions
- Conventional Commits: `feat:`, `fix:`, `chore:`, `docs:`
- Branch naming: `feat/short-description`, `fix/issue-number`
- Squash merge to main; delete branches after merge
## Notes
- The `src/legacy/` directory is being migrated. Do not add new code there.
- All dates are stored as UTC. Never use local time.
@docs/api-patterns.md
@docs/database-conventions.md
---
description: React component conventions and patterns
globs: "*.tsx"
alwaysApply: false
---
# React Component Rules
- Use functional components with explicit return types
- Define props interface directly above the component
- Export components as named exports, never default
- Use Tailwind CSS utility classes exclusively
KEY DIFFERENCES
Claude Code: markdown. Cursor: mdc.
Claude Code: Supported. Cursor: Not supported.
Claude Code: .claudeignore. Cursor: .cursorignore.
Claude Code: CLI. Cursor: Supported.
Claude Code: Free-form (Markdown). Cursor: Hybrid (MDC frontmatter + Markdown).
Claude Code concatenates CLAUDE.md files from global, project root, and subdirectories into a single context. Cursor uses individual .mdc rule files with frontmatter that controls when each rule activates (always, glob-matched, or manual).
CLAUDE.md supports @filename.md directives to include content from other files, enabling modular instruction sets. Cursor rules are self-contained per .mdc file with no cross-file referencing.
Cursor .mdc files use YAML frontmatter with description, globs, and alwaysApply fields to control rule activation. CLAUDE.md uses plain Markdown with no structured metadata — all content is always included at the appropriate scope level.
Claude Code operates as a terminal-first agent where configuration is designed for non-interactive batch workflows. Cursor is an IDE where rules augment interactive editing, chat, and code completion.
WHICH SHOULD I USE?
PORTABILITY TIP
# Maintain a single source of truth:
cp AI-INSTRUCTIONS.md CLAUDE.md
cp AI-INSTRUCTIONS.md .cursorrules
cp AI-INSTRUCTIONS.md AGENTS.md