OneMCP is a native macOS application that aggregates multiple Model Context Protocol (MCP) servers into a unified interface. It provides a seamless way to manage and interact with multiple MCP servers through a single endpoint, complete with a modern SwiftUI interface and system tray integration.
- MCP Server Aggregation: Connect and manage multiple upstream MCP servers through a unified interface
- Multi-Protocol Support: Supports Standard I/O, Server-Sent Events (SSE), and HTTP transport protocols
- Unified HTTP Endpoint: Exposes all connected servers through a single HTTP interface for downstream clients
- Real-time Status Monitoring: Live monitoring of server connections, capabilities, and performance metrics
- Native macOS App: Built with SwiftUI for a modern, native macOS experience
- System Tray Integration: Convenient menu bar access with status indicators
- Multi-Tab Interface: Organized views for Overview, Servers, Capabilities, and Logs
- Settings Management: Comprehensive configuration through a dedicated settings panel
- Capability Prefixing: Automatically prefixes capabilities from different servers to avoid naming conflicts
- Performance Monitoring: Built-in performance tracking with alerts and metrics
- Retry Logic: Configurable retry mechanisms for unreliable server connections
- CORS Support: Configurable CORS settings for web client integration
- Notifications: System notifications for server status changes and errors
- macOS 13.0 or later
- Swift 6.0+
- Xcode 15.0+ (for development)
Download the latest release from the Releases page.
-
Clone the repository:
git clone https://github.com/your-repo/onemcp.git cd onemcp -
Build the application:
make app
-
Install to Applications folder:
cp -r OneMCP.app /Applications/
For development, you can run the app directly:
make runOneMCP stores its configuration in ~/Library/Application Support/OneMCP/config.json. The application provides a graphical interface for configuration, but you can also edit the JSON directly.
OneMCP supports three types of upstream servers:
{
"id": "uuid-here",
"name": "My StdIO Server",
"type": "stdio",
"enabled": true,
"config": {
"stdio": {
"command": "/path/to/server",
"arguments": ["--arg1", "value1"],
"environment": {
"KEY": "value"
},
"workingDirectory": "/path/to/working/dir"
}
}
}{
"id": "uuid-here",
"name": "My SSE Server",
"type": "sse",
"enabled": true,
"config": {
"sse": {
"url": "http://localhost:3001/sse",
"headers": {
"Authorization": "Bearer token"
}
}
}
}{
"id": "uuid-here",
"name": "My HTTP Server",
"type": "streamable-http",
"enabled": true,
"config": {
"streamableHttp": {
"url": "http://localhost:3002",
"headers": {
"Authorization": "Bearer token"
}
}
}
}{
"server": {
"port": 3000,
"host": "localhost",
"enableCors": true
},
"ui": {
"startMinimized": false,
"showInDock": true,
"enableNotifications": true,
"theme": "system"
},
"logging": {
"level": "info",
"enableFileLogging": true,
"maxLogSize": 10000000
}
}- Launch OneMCP from the Applications folder or system tray
- The application will start the aggregation server on the configured port (default: 3000)
- Configure your upstream MCP servers through the Settings panel
- Monitor server status through the Overview tab
Once OneMCP is running, downstream clients can connect to the aggregated endpoint:
http://localhost:3000
All capabilities from connected upstream servers will be available through this single endpoint, with automatic prefixing to avoid naming conflicts.
- Server Status: Green/red indicator showing overall server status
- Quick Actions: Access to main window and settings
- Notifications: Real-time alerts for server status changes
- MCPAggregationService: Main service orchestrating server connections and capability aggregation
- UpstreamManager: Manages connections to upstream MCP servers
- HTTPServerTransport: HTTP server implementation for downstream clients
- AppState: Central state management using SwiftUI's ObservableObject
- ConfigManager: Configuration persistence and management
OneMCP supports multiple transport protocols:
- SubprocessStdioTransport: For command-line MCP servers
- LegacySSETransport: For Server-Sent Events connections
- HTTPServerTransport: For HTTP-based MCP servers
- Capabilities from different servers are prefixed with server names to avoid conflicts
- Example:
server1_tool_name,server2_tool_name - Original capability names are preserved in metadata for reference
Run the test suite:
make testOneMCP includes built-in performance monitoring:
- Connection Metrics: Active connections, total connections, error rates
- Request Metrics: Response times, success/failure rates
- Resource Usage: Memory usage tracking
- Alerts: Configurable performance alerts
- Localhost Binding: Default configuration binds to localhost for security
- CORS Configuration: Configurable CORS settings for web client integration
- Process Isolation: Upstream servers run in separate processes
- Error Isolation: Failures in one upstream server don't affect others
- Port Already in Use: OneMCP will automatically find an alternative port and notify you
- Server Connection Failures: Check server configuration and logs in the Logs tab
- Performance Issues: Monitor the Performance tab for bottlenecks
View detailed logs through:
- The Logs tab in the main interface
- Console.app (search for "OneMCP")
- Log files in
~/Library/Application Support/OneMCP/
- Fork the repository
- Create a feature branch:
git checkout -b feature/amazing-feature - Commit your changes:
git commit -m 'Add amazing feature' - Push to the branch:
git push origin feature/amazing-feature - Open a Pull Request
This project is licensed under the MIT License - see the LICENSE file for details.
- Built using the Swift MCP SDK
- Uses Swift Service Lifecycle for service management
- Logging provided by Swift Log
For support, please:
- Check the Issues page
- Create a new issue with detailed information
- Include relevant logs and configuration details
OneMCP - Simplifying MCP server management on macOS