OpenAPI to MCP Server by Tyk
TykTechnologiesLABSCO SUMMARY
Spec in, MCP tools out — with a guided path.
The differentiator against other spec-to-MCP converters is the onboarding: an interactive terminal walks you through configuration before you commit to flags, which lowers the barrier for a first run. Underneath it is the expected kit — operation filters to trim the surface, Bearer-token auth, custom headers, and a choice of stdio, SSE or Streamable transport. One wrinkle worth noting: the interactive session mode cannot start in stdio, so for a Claude Desktop-style stdio launch you pass the spec and transport as flags directly.
What it is
A tool that turns a REST API's OpenAPI or Swagger specification into MCP tools an AI client can call. It leads with a terminal-first experience: a guided interactive CLI (mss) for newcomers, and a direct command mode for scripts and AI-client integration.
What you get
- An OpenAPI or Swagger spec loaded from a URL or file —
--openapi; Swagger 2.0 is converted to OpenAPI 3.x on startup - A guided interactive terminal (
mss) for step-by-step configuration, or a one-shot non-interactive launch - The exposed operations filtered by HTTP method, path (with wildcards), operation id, status code or parameter
- Bearer-token authentication, with the token passed directly or read from an environment variable
- Custom request headers, static or from environment variables, plus a base-URL override
- Three transports — stdio, SSE and Streamable — selectable with
--transport
Requirements
Node.js 20.0.0 or higher, and pnpm 8+ recommended. Install with npm i mcp-swagger-server -g, which provides mss (interactive), and mcp-swagger-server / mcp-swagger (standard CLI for scripts and AI clients). Configuration can come from flags, a --config JSON file, or a .env file with MCP_* variables. Claude Desktop launches it as mss with --openapi and --transport stdio args. The package.json names the monorepo mcp-swagger-monorepo at 1.0.0; the published package is mcp-swagger-server. Interactive session mode does not support stdio startup — for stdio, pass --openapi ... --transport stdio directly.
Setup effort
One command — npm i mcp-swagger-server -g
USE CASES
01
Exposing a REST API to a model without writing code
Point it at the OpenAPI or Swagger spec and get callable MCP tools, converting Swagger 2.0 automatically.
02
Configuring it for the first time
Run the interactive mss terminal and follow the guided steps instead of memorising flags.
03
Limiting which operations the model can call
Filter by method, path, operation id or status code so only the intended endpoints become tools.
04
Calling an API that needs a token
Supply a Bearer token directly or from an environment variable, with custom headers if the API wants them.
BEFORE YOU INSTALL
What to know first
Requires
- mss on PATH
- Node.js ≥ 20.0.0
- pnpm ≥ 8.0.0
Where it runs
Both documented setups run the server on your machine.
INSTALLATION
Connect your client
Server setup
TERMINAL
npm i mcp-swagger-server -gMCP Clients
Claude Desktop — mss
CLAUDE DESKTOP — MSS · JSON
{
"mcpServers": {
"swagger-converter": {
"command": "mss",
"args": [
"--openapi",
"https://petstore.swagger.io/v2/swagger.json",
"--transport",
"stdio"
]
}
}
}Claude Desktop — full binary name
CLAUDE DESKTOP — FULL BINARY NAME · JSON
{
"mcpServers": {
"swagger-api": {
"command": "mcp-swagger-server",
"args": [
"--transport",
"stdio",
"--openapi",
"https://api.github.com/openapi.json"
]
}
}
}
