Guarding Architectural Boundaries with Cursor Rules

As developers increasingly rely on AI coding tools like Cursor, Claude, and GitHub Copilot, a new challenge has emerged: Architectural Drift.

AI coding agents are highly efficient at generating code, but they lack global architectural context. Without explicit guardrails, an agent might:

• Direct-import database clients into React frontend components.
• Bypassing internal API gateways or service layers.
• Introducing unauthorized third-party libraries.
• Violating clean architecture/domain-driven design boundaries.

Fortunately, you can define strict instructions for AI agents using a .cursorrules file at the root of your repository.

Defining the .cursorrules File

Here is an example .cursorrules structure tailored for a standard React frontend and Node/Next.js backend project, enforcing layer boundaries:

{
  "project_context": {
    "architecture": "Monorepo with Vite React (frontend) and Next.js (backend API)",
    "allowed_dependencies": {
      "frontend": ["react", "react-router-dom", "zustand", "lucide-react"],
      "backend": ["next", "pg", "zod", "typescript"]
    }
  },
  "architectural_rules": [
    {
      "rule": "Strict Separation of Concerns",
      "description": "Frontend components (under ArchGenieUI/) must NEVER import from or connect directly to database models or server packages.",
      "enforcement": "Reject any code changes in frontend components that attempt to import db/prisma clients or use process.env secrets."
    },
    {
      "rule": "API Gateway Enforcement",
      "description": "All frontend network communication must go through HTTP client calls to VITE_API_BASE_URL endpoints.",
      "forbidden": "No direct external service API calls from React views. Use custom hooks in src/state/ or utility fetch files."
    }
  ],
  "code_style": {
    "typescript": "Use TypeScript strictly. No 'any' types allowed. Interfaces must be declared in types/.",
    "components": "Functional components only, using Tailwind or CSS variables. Inline styles are forbidden."
  }
}

How to Scale This

Writing these files manually for complex systems can be tedious. FloDraw Architecture Guard automates this by analyzing your visual system architecture diagram and compiling it into executable .agents/ configurations (spec.json and AGENTS.md rulesets). It automatically symlinks .cursorrules and CLAUDE.md directly to .agents/AGENTS.md, ensuring all AI coding assistants (Cursor, Claude Code, and Antigravity) enforce the same architectural boundaries natively.