Momen Cursor Rules - Build Custom Frontends with Momen Backend-as-a-Service

Prebuilt Cursor rules for developing custom frontend applications powered by Momen.app as a headless Backend-as-a-Service (BaaS)

This repository contains a comprehensive set of production-ready Cursor rules that enable AI assistants (Claude, ChatGPT, etc.) to seamlessly integrate with Momen's powerful backend infrastructure. Use these rules to rapidly build full-stack applications with custom frontends while leveraging Momen's enterprise-grade PostgreSQL database, GraphQL API, actionflows, AI agents, and more.

🎯 What This Repository Provides

This repository contains 8 specialized rule files in .cursor/rules/ that teach AI assistants how to:

1. Understand Momen's Architecture - Backend structure, GraphQL endpoints, authentication
2. Query & Mutate Database - Auto-generated GraphQL schema from your data model
3. Execute Backend Logic - Actionflows for complex, multi-step operations
4. Integrate Third-party APIs - Use imported API definitions as backend relays
5. Leverage AI Agents - RAG, tool use, multi-modal I/O, structured JSON output
6. Handle Payments - Stripe integration for one-time and subscription billing
7. Manage Binary Assets - Image/file uploads and management
8. Fetch Project Schema - MCP server integration for real-time schema access

📦 Included Rule Files

.cursor/rules/
├── momen-backend-architecture.mdc      # Core architecture & GraphQL setup
├── momen-database-gql-api-rules.mdc    # Database CRUD operations
├── momen-actionflow-gql-api-rules.mdc  # Backend workflows & business logic
├── momen-tpa-gql-api-rules.mdc         # Third-party API integration
├── momen-ai-agent-gql-api-rules.mdc    # AI agent capabilities
├── momen-stripe-payment-rules.mdc      # Payment processing
└── momen-binary-asset-upload-rules.mdc # File management

🚀 Quick Start

Prerequisites

• Cursor Editor or any AI assistant supporting Cursor rules
• A Momen.app account and project
• Basic knowledge of GraphQL and TypeScript/JavaScript

Step 1: Build Your Backend in Momen

Before using these rules, you need to create your backend infrastructure in Momen:

1. Sign up at Momen.app and create a new project
2. Design your database - Create tables, define relationships, and set up your data model
3. Build backend logic - Create actionflows for complex business logic
4. Configure integrations - Set up Stripe payments, AI agents, third-party APIs as needed
5. Note your credentials:
   • Your Momen username (email)
   • Your Momen password
   • Your project's exId (found in project settings) or project name

Tip: Momen's visual editor makes it easy to design your entire backend without code. Once ready, use these Cursor rules to build a custom frontend that connects to your Momen backend!

Step 2: Clone This Repository

git clone https://github.com/privateJiangyaokai/momen-cursor-rules.git
cd momen-cursor-rules

Step 3: Copy Rules to Your Project

Copy the entire .cursor directory into your project root:

cp -r .cursor /path/to/your/project/

Step 4: Configure MCP Server

The MCP server allows AI to automatically fetch your project's latest schema. To configure in Cursor:

1. Open Cursor Settings (⌘ + , on macOS, Ctrl + , on Windows)
2. Search for "MCP" or navigate to Features → Model Context Protocol
3. Click "Edit Config" or "Add MCP Server"
4. Add the Momen MCP server configuration:

{
  "mcpServers": {
    "momen": {
      "command": "npx",
      "args": [
        "-y",
        "momen-mcp@latest"
      ]
    }
  }
}

Alternative: You can also manually edit the MCP config file:

• macOS: ~/Library/Application Support/Cursor/User/globalStorage/mcp-config.json
• Windows: %APPDATA%\Cursor\User\globalStorage\mcp-config.json

Note: The MCP server integration enhances AI's ability to understand your Momen project schema but is optional. The core Cursor rules work without it.

Step 5: Vibe the Frontend

Open your project in Cursor and provide AI with your Momen credentials to start building. Use prompts like:

Initial Setup:

My Momen project is:  my-ecommerce-app (or exId: abc123xyz)

Build an ecommerce website based on the Momen project's backend structure. 
Use username authentication. 

+ Other misc requirements
e.g. Use Stripe publishable key: pk_t…[redacted]

The AI will use your credentials to authenticate, fetch your project schema, and generate production-ready code that perfectly matches your Momen backend structure!

🏗️ What is Momen?

Momen is a next-generation full-stack no-code platform with a powerful backend designed for headless use. While Momen provides a visual editor for building complete applications, its backend can be used independently as a Backend-as-a-Service (BaaS) for custom frontend development.

Why Use Momen as BaaS?

✅ Enterprise-Grade PostgreSQL - Powerful relational database with full ACID compliance
✅ Auto-Generated GraphQL API - Your data model automatically becomes a type-safe GraphQL schema
✅ Built-in Backend Logic - Actionflows for complex workflows without writing backend code
✅ Native AI Integration - Built-in AI agents with RAG, tool use, and structured output
✅ Third-party API Relay - Import OpenAPI specs, use as backend relay with authentication
✅ Stripe Integration - Native payment processing for subscriptions and one-time charges
✅ File Storage - Image and binary asset management with CDN
✅ Authentication - Built-in user management with JWT tokens
✅ Real-time Subscriptions - WebSocket support via GraphQL subscriptions
✅ Predictable Pricing - Project-based pricing, no per-request charges

🎓 What are Cursor Rules?

Cursor Rules (.cursor/rules/*.mdc files) are specialized instructions that teach AI assistants about your project's architecture, APIs, and best practices. They enable AI to:

🎓 What are Cursor Rules?

Cursor Rules (.cursor/rules/*.mdc files) are specialized instructions that teach AI assistants about your project's architecture, APIs, and best practices. They enable AI to:

• Generate accurate code without extensive prompting
• Understand complex backend architectures
• Follow best practices automatically
• Produce production-ready code on first attempt

Why MDC Format?

The .mdc (Markdown with frontmatter) format includes metadata that helps AI understand when and how to apply rules:

---
description: Brief description of the rule
alwaysApply: true  # or false for contextual rules
---

# Rule content in markdown...

📚 Detailed Rule Documentation

1. momen-backend-architecture.mdc

Purpose: Core architecture understanding - always applied
Teaches AI:

• GraphQL API endpoints (HTTP & WebSocket)
• Apollo Client + subscriptions-transport-ws setup
• Authentication token handling
• Project structure and conventions

Key Concepts:

// HTTP endpoint
https://villa.momen.app/zero/{projectExId}/api/graphql-v2

// WebSocket endpoint
wss://villa.momen.app/zero/{projectExId}/api/graphql-subscription

2. momen-database-gql-api-rules.mdc

Purpose: Database operations via auto-generated GraphQL schema
Teaches AI:

• How database tables map to GraphQL types
• Query patterns for fetching data
• Mutation patterns for CRUD operations
• Relationship handling (1:1, 1:N, N:N)
• Filter, sort, and pagination syntax

Example AI can generate:

query GetPostsWithAuthors($limit: Int) {
  post(limit: $limit, order_by: {created_at: desc}) {
    id
    title
    content
    author {  # Relationship automatically handled
      id
      name
      email
    }
  }
}

3. momen-actionflow-gql-api-rules.mdc

Purpose: Execute complex backend workflows
Teaches AI:

• Sync vs async actionflows
• Invoking actionflows via GraphQL
• Handling actionflow arguments and return values
• Polling for async actionflow completion
• Error handling and retries

Use Cases:

• Multi-step business logic
• Long-running operations (LLM API calls)
• Database transactions with rollback
• Email sending, notifications
• Complex data transformations

4. momen-tpa-gql-api-rules.mdc

Purpose: Third-party API integration
Teaches AI:

• Using imported OpenAPI definitions
• Backend acts as authenticated relay
• No CORS issues
• Secure credential management

Benefits:

• Keep API keys server-side
• Centralized error handling
• Request/response logging
• Rate limiting control

5. momen-ai-agent-gql-api-rules.mdc

Purpose: Leverage built-in AI capabilities
Teaches AI:

• Creating and managing AI agents
• RAG (Retrieval Augmented Generation)
• Tool use / function calling
• Multi-modal input (text, images, audio)
• Structured JSON output
• Streaming responses

Example AI Agent Features:

• Document Q&A with vector search
• Image analysis and generation
• Automated decision making
• Data extraction from unstructured text

6. momen-stripe-payment-rules.mdc

Purpose: Payment processing integration
Teaches AI:

• One-time payment flows
• Subscription management
• Webhook handling for payment events
• Order creation and status tracking
• Stripe checkout UI integration

Supported Operations:

• Create payment intents
• Handle 3D Secure authentication
• Manage subscriptions (create, upgrade, cancel)
• Process refunds
• Handle payment failures

7. momen-binary-asset-upload-rules.mdc

Purpose: File and image management
Teaches AI:

• Direct file uploads to Momen storage
• Image optimization and transformation
• CDN URL generation
• File metadata management
• Access control for assets

Supported File Types:

• Images (JPG, PNG, GIF, WebP)
• Documents (PDF, DOCX, XLSX)
• Videos (MP4, WebM)
• Audio files
• General binary data

Generated Files:

.momen-mcp/
├── credentials.json
└── config.json

💡 Usage Examples

Example 1: Building a Blog with AI Assistant

You: "Create a Next.js blog based on the Momen project's backend whose exId is abc91xyY"

🛠️ Advanced Workflows

Combining Multiple Rules

The rules work together intelligently. For example:

You: "Build a social media post creation flow with image upload and Stripe payment for premium features"

AI will use:

• momen-backend-architecture.mdc → Set up Apollo Client
• momen-database-gql-api-rules.mdc → Create post mutation
• momen-binary-asset-upload-rules.mdc → Handle image upload
• momen-actionflow-gql-api-rules.mdc → Multi-step post creation workflow
• momen-stripe-payment-rules.mdc → Premium feature paywall
• momen-ai-agent-gql-api-rules.mdc → AI-powered content moderation

🎯 Best Practices

1. Rule Selection

Rules have alwaysApply metadata:

• true: AI always considers this rule (e.g., architecture)
• false: AI applies contextually when relevant

2. Keep Schema Updated

Use MCP server to refresh schema whenever your Momen project structure changes:

You: "Refresh my Momen project's schema"
AI: Fetches project's latest schema into context

3. Leverage Actionflows for Complex Logic

Don't try to implement multi-step business logic in frontend:

❌ Don't:

// Frontend doing too much
const createOrderWithInventoryCheck = async () => {
  const inventory = await checkInventory(productId);
  if (inventory > 0) {
    const order = await createOrder(...);
    await reduceInventory(productId);
    await sendEmail(...);
  }
};

✅ Do:

// Let backend actionflow handle it
const createOrder = async () => {
  awa