mcpwrap

Live: https://mcp-forge-black.vercel.app

Turn any REST API into an MCP server in 10 seconds.

npx mcpwrap --spec https://petstore3.swagger.io/api/v3/openapi.json

No code generation. No config files. Just point and serve.

Why?

Other tools generate static code from your OpenAPI spec. mcpwrap wraps your API at runtime - it reads the spec, creates MCP tools dynamically, and proxies requests to your API. Update the spec, restart, done.

Quick Start

# From a URL
npx mcpwrap --spec https://api.example.com/openapi.json

# From a local file
npx mcpwrap --spec ./my-api.yaml

# With authentication
npx mcpwrap --spec ./api.json --auth "Bearer $MY_TOKEN"

# With API key header
npx mcpwrap --spec ./api.json --auth "X-API-Key:your-key-here"

# Filter endpoints
npx mcpwrap --spec ./api.json --include "/pets/*" --exclude "/admin/*"

Claude Desktop Integration

Add to your Claude Desktop config (claude_desktop_config.json):

{
  "mcpServers": {
    "my-api": {
      "command": "npx",
      "args": ["mcpwrap", "--spec", "https://api.example.com/openapi.json"]
    }
  }
}

How It Works

1. Reads your OpenAPI 3.0/3.1 spec (JSON or YAML, local or remote)
2. Parses every endpoint into an MCP tool (one tool per operation)
3. Maps parameters and request bodies to MCP tool input schemas
4. Proxies tool calls to your API and returns the response
5. Flattens large/nested responses for LLM readability

Features

• Runtime wrapping - no generated code to maintain
• OpenAPI 3.0 and 3.1 support
• All HTTP methods - GET, POST, PUT, DELETE, PATCH
• Auth passthrough - Bearer tokens, API keys, Basic auth
• Path and query params - automatically mapped from tool arguments
• Request body - JSON body passed as body argument
• Response flattening - truncates deep nesting and long arrays
• Endpoint filtering - include/exclude by path pattern
• Verbose mode - logs requests to stderr for debugging

CLI Options

Option	Description	Default
--spec <path>	Path or URL to OpenAPI spec (required)	-
--base-url <url>	Override base URL from spec	From spec
--auth <auth>	Auth: Bearer TOKEN, HEADER:VALUE	None
--include <patterns>	Only include matching paths	All
--exclude <patterns>	Exclude matching paths	None
--transport <type>	stdio or http	stdio
--port <number>	Port for HTTP transport	3100
--no-flatten	Disable response flattening	Enabled
--verbose	Log requests to stderr	Off

Tool Naming

Tools are named using the operationId from your spec when available, falling back to METHOD_path_segments (e.g., get_pets_petId).

Development

git clone https://github.com/m4cd4r4/mcpwrap
cd mcpwrap
npm install
npm test
npm run dev -- --spec examples/petstore.json --verbose

License

MIT