Every AI coding tool reads project-specific instructions from config files. This reference covers all major tools so you can configure your project once and support multiple workflows.
Project file: CLAUDE.md in project rootGlobal file: ~/.claude/CLAUDE.mdNested support: Yes - place CLAUDE.md in subdirectories for module-specific context
# Project: My App## Tech Stack- TypeScript, React, Node.js- PostgreSQL with Prisma ORM## Conventions- Use functional components with hooks- Prefer named exports- Tests in `__tests__/` directories## Commands- `npm run dev` - Start development- `npm test` - Run tests
Project file: GEMINI.md in project rootGlobal file: ~/.gemini/GEMINI.mdNested support: Yes - place GEMINI.md in subdirectories
# Project: My App## Tech Stack- TypeScript, React, Node.js- PostgreSQL with Drizzle ORM## Conventions- Use functional components- Prefer named exports- Co-locate tests with source files## Sandbox- Use `npm run dev` for development- Database runs in Docker
Project file: AGENTS.md in project rootGlobal file: ~/.opencode/AGENTS.mdNested support: Yes - each directory can have its own AGENTS.md
# Project Instructions## OverviewThis is a Next.js e-commerce application.## Architecture- `/app` - Next.js App Router pages- `/lib` - Shared utilities- `/components` - React components## Rules- Use TypeScript strict mode- All API routes must validate input with Zod- Use server actions for mutations
Project file: .cursorrules in project rootGlobal rules: Settings → General → Rules for AINested support: Yes - .cursor/rules/*.md for additional rules
You are an expert TypeScript developer.## Code Style- Use functional programming patterns- Prefer immutability- Use early returns## Project Structure- Components in `/src/components`- Hooks in `/src/hooks`- Types in `/src/types`## Testing- Use Vitest for unit tests- Use Playwright for E2E- Minimum 80% coverage
Project file: .github/copilot-instructions.mdGlobal config: Not supported (VS Code settings only)Nested support: No
project/└── .github/ └── copilot-instructions.md
Example content:
## Project ContextThis is a Python FastAPI backend service.## Coding Standards- Use type hints for all functions- Follow PEP 8 style guide- Use pydantic for data validation## Preferences- Prefer async/await for I/O operations- Use dependency injection pattern- Write docstrings for public functions
# Code Conventions## Formatting- 2 space indentation- Single quotes for strings- Trailing commas## Naming- camelCase for variables- PascalCase for components- SCREAMING_SNAKE for constants
# Codex Instructions## ProjectReact Native mobile app with Expo## Guidelines- Use Expo SDK features when available- Handle offline state gracefully- Support iOS and Android equally## Commands- `npx expo start` - Development- `npx expo build` - Production build