Free tool
Rules file converter
Write a rule once and use it in every coding agent your team runs. Paste a rule in any agent's format and get the file path and frontmatter for 11 targets, keeping when the rule applies. Formats checked against each vendor's docs on 2026-10-19. Nothing leaves your browser.
Scope: Only for matching files (src/**/*.ts, test/**/*.ts)
Detected from: globs
Convert to
Save as: .cursor/rules/nestjs.mdc
--- globs: src/**/*.ts, test/**/*.ts alwaysApply: false --- - Organize code by feature module; each module declares its controllers and providers and exports only what others need. - Inject dependencies through constructors; never instantiate services with new. - Keep controllers thin: map HTTP to service calls and put business logic in services. - Define request bodies as DTO classes with class-validator decorators and enable a global ValidationPipe with whitelist: true. - Throw built-in HTTP exceptions (NotFoundException, BadRequestException) instead of returning error objects. - Use guards for auth, interceptors for cross-cutting concerns and exception filters for error formatting. - Read configuration through ConfigService from @nestjs/config, not process.env scattered across files. - Generate pieces with the Nest CLI (nest g) and test providers with Test.createTestingModule.
Format source: Cursor docs.
How scope maps between agents
| When it applies | Cursor .mdc | Claude Code | GitHub Copilot | Kiro | Antigravity / Devin |
|---|---|---|---|---|---|
| Always on | alwaysApply: true | no paths | applyTo: "**" | inclusion: always | trigger: always_on |
| Matching files | globs | paths | applyTo | inclusion: fileMatch | trigger: glob |
| Agent decides | description | (use a Skill) | description (VS Code) | inclusion: auto | trigger: model_decision |
| Manual | no description, no globs | (use a Skill) | neither (VS Code) | inclusion: manual | trigger: manual |
AGENTS.md, GEMINI.md and Codex have no frontmatter: put the file in the folder it applies to. Zed reads only the first instruction file it finds, so a .cursorrules file wins over AGENTS.md there.
Related
Rules formats keep changing
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