OpenAPI MCP server

The OpenAPI MCP Server provides a standardized interface for interacting with model services through a RESTful API. It implements the Model Context Protocol (MCP) specification and can be quickly configured from your OpenAPI documentation.

Overview

This server allows you to easily create an MCP server with StreamableHTTP transport implementation based on your existing OpenAPI documentation. Simply configure an environment file and the server is ready to run.

Prerequisites

• Node.js (v20 or higher)
• npm (v6 or higher)

Installation

1. Clone the repository:

   git clone https://github.com/oneWalker/openapi-mcp-server.git
   cd openapi-mcp-server
   

2. Install dependencies:

   npm install
   

3. Configure environment: Create a .env file in the project root with your configuration settings.

4. Run the server:

   npm run build
   npm run start
   

Configuration

Create a .env file in the root directory with the following settings:

# The base URL for the original API server
BASE_SERVER_URL=https://api.example.com

# The path to the OpenAPI specification file (can be a local file or a URL)
OPENAPI_PATH=./example.yaml or ./example.json

# The port for the MCP server to run on
PORT=8000

API Endpoints

Get Model Service API Documentation

Retrieve API documentation for a specific model service:

GET /api/model/services/{ID}

Parameters:

• ID (path, required): Model service ID
• authorization (header, required): Bearer token for authentication

Call Model Service

Invoke a specific model service with provided parameters:

POST /api/model/services/

Parameters:

• id (path, required): Model service ID

Request Body Example:

{
  "id": "123"
}

Running in Development Mode

To run the server in development mode with automatic reloading:

npm run watch

How to install this MCP server

For Claude Code

To add this MCP server to Claude Code, run this command in your terminal:

claude mcp add-json "openapi" '{"command":"npx","args":["-y","openapi-mcp-server"]}'

See the official Claude Code MCP documentation for more details.

For Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > Tools & Integrations and click "New MCP Server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "openapi": {
            "command": "npx",
            "args": [
                "-y",
                "openapi-mcp-server"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explicitly ask the agent to use the tool by mentioning the tool name and describing what the function does.

For Claude Desktop

To add this MCP server to Claude Desktop:

1. Find your configuration file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

2. Add this to your configuration file:

{
    "mcpServers": {
        "openapi": {
            "command": "npx",
            "args": [
                "-y",
                "openapi-mcp-server"
            ]
        }
    }
}

3. Restart Claude Desktop for the changes to take effect