REST-to-Postman MCP

A Model Context Protocol (MCP) server that converts REST API code (e.g., NestJS controllers, FastAPI/Flask endpoints) to Postman collections and environments. This tool helps developers automatically sync their REST API endpoints and environment configurations with Postman.

Features

• Convert REST API endpoints to Postman collections
• Sync environment variables with Postman environments
• Support for various authentication methods (e.g., Bearer token)
• Intelligent merging of new endpoints with existing collections
• Automatic handling of sensitive environment variables
• Support for both stdio and SSE transport modes

Prerequisites

• Bun v1.2.2 or later
• Postman API Key
• Postman Workspace ID

Installation & Usage

This is a Model Context Protocol (MCP) stdio server that requires access to your Postman workspace to create/update collections and environments.

Installing via Smithery

To install REST-to-Postman MCP for Claude Desktop automatically via Smithery:

npx -y @smithery/cli install @runninghare/rest-to-postman-mcp --client claude

Running the MCP Server with npx

To use the MCP server with npx:

npx -y rest-to-postman@latest --postman-api-key your_api_key --postman-workspace-id your_workspace_id

Or use environment variables:

export POSTMAN_API_KEY=your_api_key
export POSTMAN_ACTIVE_WORKSPACE_ID=your_workspace_id
npx -y rest-to-postman@latest 

You can integrate this command with various AI code editors that support MCP:

• Claude Desktop
• Cursor
• Windsurf
• Roo Cline Editor

Important Note: The server requires Postman API credentials to function. Make sure you have both the API key and workspace ID ready before starting the server.

Tool Descriptions

The server provides two main tools:

1. REST to Postman Environment (rest_to_postman_env)

Creates or updates a Postman environment with your application's environment variables.

Input Parameters:

• envName (string): Name of the Postman environment
• envVars (object): Key-value pairs of environment variables

Example Input:

{
    "envName": "REST Environment",
    "envVars": {
        "API_URL": "https://api.example.com",
        "API_TOKEN": "secret-token-1"
    }
}

2. REST to Postman Collection (rest_to_postman_collection)

Creates or updates a Postman collection with your REST API endpoints.

Input Parameters:

• collectionRequest (object): Postman collection configuration containing:
  • info: Collection metadata
  • auth: Authentication settings
  • item: Array of API endpoints

Example Input:

{
    "info": {
        "name": "REST Collection",
        "description": "REST Collection", 
        "schema": "https://schema.getpostman.com/json/collection/v2.1.0/collection.json"
    },
    "auth": {
        "type": "bearer",
        "bearer": [
            {   
                "key": "Authorization",
                "value": "Bearer {{API_TOKEN}}",
                "type": "string"
            }
        ]
    },  
    "item": [
        {
            "name": "Get Users",
            "request": {
                "method": "GET",    
                "url": {
                    "raw": "{{API_URL}}/users",
                    "protocol": "https",
                    "host": ["api", "example", "com"],
                    "path": ["users"]
                }   
            }
        }
    ]
}

Response Format

Both tools return a success message confirming the creation/update of the Postman resource:

{
    "content": [{
        "type": "text",
        "text": "Successfully created/updated Postman environment: REST Environment"
    }]
}

Use this MCP in Cursor

You can use this MCP server in Cursor. Here's an example which generates a Postman Collection based on a Nest.js Typescript controller.

Prompt:

Create a postman collection named "Campaign Endpoints" based on this next.js controller. The baseUrl is `http://localhost:7022`. The collection should have a Bear token which applies to all the endpoints

Here's the automatically generated Postman Collection:

Note all the endpoints from the Campaign Controller are generated, along with the Bear token setting.

Development

Local Setup

1. Clone the repository:

git clone https://github.com/runninghare/rest-to-postman.git
cd rest-to-postman

2. Install dependencies:

bun install

3. Create a .env file:

POSTMAN_API_KEY=your_api_key_here
POSTMAN_ACTIVE_WORKSPACE_ID=your_workspace_id_here

Running in Development Mode

For development, you can run the server directly using Bun:

# Start in stdio mode (default)
bun run src/mcp.ts

# Start in SSE mode
bun run src/mcp.ts --sse

Building

To build the project:

bun run build

This will create a bundled output in the dist directory.

Scripts

• bun run build - Build the project
• bun run dev - Run the server in development mode
• bun run startSSE - Start the server in SSE mode

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details.