mcp-gateway

mcp-gateway

3.2

If you are the rightful owner of mcp-gateway and would like to certify it and/or have it hosted online, please leave a comment on the right or send an email to henry@mcphub.com.

MCP Gateway translates MCP tool calls to traditional HTTP API requests, providing a configurable way to integrate existing HTTP APIs into the MCP ecosystem.

MCP Gateway

MCP (Model Context Protocol) Gateway can translate MCP tool callings to traditional HTTP API requests. It can provide a configurable way to get existing HTTP API to MCP territory.

Getting Started

Create config file from config.example.yaml:

$ cp config.example.yaml config.yaml

Edit config.yaml file, map all APIs to MCP tools.

Then start launch it with SSE transport:

$ uv run mcp-gateway
INFO:     Started server process [15400]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     Uvicorn running on http://0.0.0.0:3001 (Press CTRL+C to quit)

Default is 3001.

Server Control

Change Port

Provide parameter --port=<port_no> in command line will change the port to SSE transport.

Launch gateway with port 3002:

$ uv run mcp-gateway --port=3002
INFO:     Started server process [15400]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     Uvicorn running on http://0.0.0.0:3002 (Press CTRL+C to quit)

stdio Transport

Provide parameter --transport=stdio in command line will change the transport to stdio.

E.G.:

$ uv run mcp-gateway --transport=stdio

It's meaningless to manually launch gateway in stdio transport. You can configure in Cursor or Cline like:

{
    "mcpServers": {
        "mcp-gateway": {
          "command": "uv",
          "args": ["run", "mcp-gateway", "--transport=stdio"]
        }
      }
}

Or MCP Inspector with form values:

ItemValue
Transport TypeSTDIO
Commanduv
Argumentsrun mcp-gateway --transport=stdio

Configuration File

There is two parts in configuration YAML, server and tools. server defines the basic info for gateway server use. tools defines the mapping from single MCP tool to HTTP API request.

server:
  name: rest-amap-server
  config:
    apiKey: foo
tools:
- name: maps-geo
  description: "将详细的结构化地址转换为经纬度坐标。支持对地标性名胜景区、建筑物名称解析为经纬度坐标"
  args:
  - name: address
    description: "待解析的结构化地址信息"
    required: true
  - name: city
    description: "指定查询的城市"
    required: false
  requestTemplate:
    url: "https://restapi.amap.com/v3/geocode/geo?key={{.config.apiKey}}&address={{.args.address}}&city={{.args.city}}&source=ts_mcp"
    method: GET
    headers:
    - key: x-api-key
      value: "{{.config.apiKey}}"
    - key: Content-Type
      value: application/json
  responseTemplate:
    body: |
      # 地理编码信息
      {{- range $index, $geo := .Geocodes }}
      ## 地点 {{add $index 1}}

      - **国家**: {{ $geo.Country }}
      - **省份**: {{ $geo.Province }}
      - **城市**: {{ $geo.City }}
      - **城市代码**: {{ $geo.Citycode }}
      - **区/县**: {{ $geo.District }}
      - **街道**: {{ $geo.Street }}
      - **门牌号**: {{ $geo.Number }}
      - **行政编码**: {{ $geo.Adcode }}
      - **坐标**: {{ $geo.Location }}
      - **级别**: {{ $geo.Level }}
      {{- end }}

Server

ItemDescription
nameServer name
configKey/Value pairs that can be referenced by var {{.config.xxx}} in templates

Tools

tools is list of MCP tools mapping. Single tool props. are defined as follows:

ItemDescription
nameTool name (Function name), which is provided to LLM.
descriptionTool description through which LLM can understand what the tool could do.
argsArguments of tool (Function arguments).
requestTemplateRequest mapping to target HTTP API.
responseTemplateResponse mapping for response of target HTTP API.

Single argument props. are defined as follows:

ItemTypeDescription
nameArgument name, which is provided to LLM.
descriptionArgument description through which LLM can understand and decide what value should be filled.
requiredBooleanRequired argument or not.

Request template props. are defined as follows:

ItemDescription
methodHTTP method
urlTarget HTTP API url template
headersHTTP headers

HTTP headers are defined as follows:

ItemDescription
keyHeader key
valueHeader value template

Response template props are defined as follows:

ItemDescription
bodyResponse body template

Contribution

All kinds of contribution are welcomed.