OpenAPI Proxy MCP server

The OpenAPI MCP Server enables searching and exploring OpenAPI specifications through oapis.org using the Model Context Protocol (MCP). This server allows Claude and Cursor to analyze API documentation, summarize specifications, and provide detailed endpoint information in simple language.

Features

• Get comprehensive overviews of any OpenAPI specification
• Access specific API operation details
• Support for both JSON and YAML formats
• Compatible with Claude Desktop and Cursor

Installation

You can use the OpenAPI MCP Server with Claude Desktop or Cursor by configuring the MCP URL:

https://openapi-mcp.openapisearch.com/mcp

For Claude Desktop

1. Open Claude Desktop
2. Go to Settings
3. Navigate to the Contexts or Extensions section
4. Add a new MCP context
5. Enter the MCP URL: https://openapi-mcp.openapisearch.com/mcp
6. Save the configuration

For Cursor

1. Launch Cursor
2. Access the settings menu
3. Look for MCP configurations
4. Add the OpenAPI MCP Server using the URL: https://openapi-mcp.openapisearch.com/mcp
5. Save your changes

Usage

Once configured, you can interact with OpenAPI specifications through the MCP server using natural language queries.

Basic Examples

• "Show me the Stripe API documentation"
• "Explain how authentication works in the GitHub API"
• "What endpoints are available in the Twitter API?"
• "How do I create a new user in the Auth0 API?"

How It Works

The MCP server follows a three-step process when handling your queries:

1. It identifies the required OpenAPI specification identifier
2. It generates a plain language summary of the specification
3. It determines relevant endpoints for your query and explains how they work in simple terms

Running Locally for Testing

If you want to test the server locally:

1. Start the server using Wrangler:

wrangler dev

2. Run the MCP inspector in another terminal:

npx @modelcontextprotocol/inspector

This allows you to test your queries against the local server before using it with Claude or Cursor.

Additional Resources

• Demo: View on X/Twitter
• HN Thread: Hacker News Discussion
• Related Projects:
  • OpenAPISearch: GitHub Repository
  • OAPIS: GitHub Repository

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-mcp-server" '{"command":"npx","args":["openapi-mcp-server@latest"]}'

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-mcp-server": {
            "command": "npx",
            "args": [
                "openapi-mcp-server@latest"
            ]
        }
    }
}

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-mcp-server": {
            "command": "npx",
            "args": [
                "openapi-mcp-server@latest"
            ]
        }
    }
}

3. Restart Claude Desktop for the changes to take effect