mcp-rest

MCP REST Bridge

The MCP REST Bridge allows you to expose any OpenAPI endpoint through the MCP protocol without additional coding or testing. Your existing REST API can be seamlessly accessed by AI tools like Anthropic, Cursor, and Windsurf via MCP.

Core functionality

• sse/stdio transports
• OpenAPI authentication via headers
• Including and excluding paths from the API
• Custom base url for accessing API

Local usage

1. Install mcp-rest

npm install mcp-rest

2. Running MCP server

sse mode

npx mcp-rest \
    --mode sse \
    --api-spec-url "https://api.example.com/v1/openapi.json" 

stdio mode

npx mcp-rest \
    --mode stdio \
    --api-spec-url "https://api.example.com/v1/openapi.json" 

Configuration

Configuration can be provided via environment variables or command line arguments. Environment variables take precedence over command line arguments.

The REST Bridge supports filtering which endpoints from the OpenAPI specification will be exposed as MCP tools, allowing you to control access to specific API endpoints based on your needs.

Environment Variable	Command Line Argument	Description
MODE	--mode	Run mode (sse or stdio), required
API_SPEC_URL	--api-spec-url	URL of the OpenAPI specification, required
API_BASE_URL	--api-base-url	Base URL for API requests
INCLUDE_ENDPOINTS	--include-endpoints	Comma-separated list of endpoints to include. Format <PATH>:<METHOD>. Wildcard is supported in match all paths for a method *:GET or all methods for a path /user/{id}:*
EXCLUDE_ENDPOINTS	--exclude-endpoints	Comma-separated list of endpoints to exclude. Same format as include endpoints.
AUTHENTICATION	--authentication	Authentication in format <type>:<value> where type is one of: Api-Key, X-Api-Key, Bearer, JWT, or Basic

NOTE: when using --include-endpoints and --exclude-endpoints, first included endpoints are added to candidates list and then excluded endpoints will be removed from the candidates list.

Development details

• FastMCP - MCP server framework
• Release management - release and version management
• Git Hooks
  • lint-staged - linting and formatting
  • commitlint - ensure that commit messages follow Conventional Commits schema

TODO

• [ ] - Serve binary content
• [ ] - Improve test coverage
• [ ] - Configure endpoints to be exposed as resources
• [ ] - File-based extended configuration