OpenAPI MCP Server

A Model Context Protocol (MCP) server for Claude/Cursor that enables searching and exploring OpenAPI specifications through oapis.org.

• Demo: https://x.com/janwilmake/status/1903497808134496583
• HN Thread: https://news.ycombinator.com/item?id=43447278
• OpenAPISearch: https://github.com/janwilmake/openapisearch
• OAPIS: https://github.com/janwilmake/oapis

The MCP works by applying a 3 step process :

1. It figures out the openapi identifier you need
2. It requests a summary of that in simple language
3. It determines which endpoints you need, and checks out how exactly they work (again, in simple language)

[!IMPORTANT] OpenAPI MCP has found a new owner and has been migrated from v1.2 to v2, which works different to the previous version. You can still access any version prior to v2.0.0 and their README is here

OpenAPI MCP v2 is a Work In Progress and focuses on exploration and providing context about APIs. It does not allow executing the endpoints as tools directly, as authentication isn't a solved problem with MCP yet. However, it's great for codegen!

Expect bugs. Open To Contributers, DM

Features

• Get an overview of any OpenAPI specification
• Retrieve details about specific API operations
• Support for both JSON and YAML formats
• Tested with Claude Desktop and Cursor

| Summary | Prompt it | | --------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Basic understanding of the OpenAPI MCP Server | | | Core implementation details of the MCP server | | | How to extend or contribute to the project | |

Installation

Installing via Smithery

To install openapi-mcp-server for Claude Desktop automatically via Smithery:

npx -y @smithery/cli install @janwilmake/openapi-mcp-server --client claude

Installing using stdio

{
  "mcpServers": {
    "openapi-mcp-server": {
      "command": "node",
      "args": ["/absolute/path/to/openapi-mcp-server/index.js"],
      "env": {
        "DEBUG": "true"
      }
    }
  }
}

Usage in Claude

Once installed, you can ask Claude to:

• "Find information about the Stripe API"
• "Explain how to use the GitHub API's repository endpoints"

Claude will use the MCP server to:

1. First get an overview of the requested API
2. Then retrieve specific operation details as needed

Requirements

• Node.js >= 16.17.0
• Claude Desktop, Cursor, or any other MCP client.

License

MIT