McpHub

McpHub

MCP bridge -- folds the capabilities (tools / prompts / resources) of multiple MCP servers into 4 fixed tools, exposed uniformly to AI tools.

Quick Start

stdio mode (default)

dotnet run --project src/McpHub -- --config examples/mcp-hub.config.json

Configure in your AI tool's mcp.json:

{
  "servers": {
    "mcp-hub": {
      "command": "dotnet",
      "args": [
        "run",
        "--project", "path/to/McpHub",
        "--", "--config", "path/to/mcp-hub.config.json"
      ]
    }
  }
}

HTTP mode

dotnet run --project src/McpHub -- --http --port 8080 --config examples/mcp-hub.config.json

Client connects to http://localhost:8080/ (Streamable HTTP).

CLI Options

Option	Alias	Description	Default
--config	-c	Path to the MCP configuration file	Auto-discovered
--http	-	Use HTTP (Streamable HTTP) transport	stdio
--port	-	HTTP mode listening port	8080
--workspace	-w	Workspace folder for ${workspaceFolder} substitution	Current directory
--verbose	-	Output verbose diagnostic logs to stderr	Off

暴露的 3 个 Tool

Tool	说明
list_mcp_capabilities	列出所有上游 MCP server 的可用能力（tools/prompts/resources），可选 kind 过滤
describe_mcp_capability	查询某个能力的完整调用方式（参数 schema 等），输入限定名 serverName.capabilityName
call_mcp_capability	实际调用某个能力，传入限定名 + arguments

配置文件格式

兼容 VS Code 族（servers 键）和 Claude/Cursor 族（mcpServers 键），自动推断 transport 类型：

{
  "servers": {
    "filesystem": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem", "/path"],
      "env": { "API_KEY": "..." }
    },
    "remote-server": {
      "type": "http",
      "url": "https://example.com/mcp",
      "headers": { "Authorization": "Bearer xxx" }
    }
  }
}

支持变量替换：

• ${workspaceFolder} — 工作区目录
• ${env:VAR_NAME} — 环境变量

配置文件发现顺序（未指定 --config 时）：

1. --config 显式指定
2. 当前目录 mcp.json
3. 当前目录 .mcp.json
4. .vscode/mcp.json
5. claude_desktop_config.json

架构

AI 工具  ←stdio/http→  McpHub  ←stdio/http→  多个上游 MCP Server
                         │
                         ├── list_mcp_capabilities  → 聚合所有 server 的 tools/prompts/resources
                         ├── describe_mcp_capability → 透传 schema 详情
                         └── call_mcp_capability     → 透传调用

详见 设计文档。