Mcp4go

🚀 MCP4Go

MCP4Go is a pure Go implementation of the Model Context Protocol (MCP), aiming to simplify the development of AI applications by abstracting protocol complexity.

🚀 Quick Start

To get started with MCP4Go, import the package into your Go application:

package main

import (
	"context"
	"fmt"
	"log"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/mcp4go/mcp4go/pkg/logger"
	"github.com/mcp4go/mcp4go/protocol"
	"github.com/mcp4go/mcp4go/server"
	"github.com/mcp4go/mcp4go/server/iface"
	"github.com/mcp4go/mcp4go/server/transport"

	_ "time/tzdata" // Load all time zones
)

func main() {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()
	_logger := logger.DefaultLog

	// Listen for interrupt signals for graceful shutdown
	signalCh := make(chan os.Signal, 1)
	signal.Notify(signalCh, os.Interrupt, syscall.SIGTERM)
	go func() {
		<-signalCh
		_logger.Logf(ctx, logger.LevelWarn, "Received shutdown signal")
		cancel()
	}()

	type timeRequest struct {
		TimeZone string `json:"time_zone,omitempty" description:"Time zone, default is Asia/Shanghai"`
	}

	// Create a standard input/output transport layer
	stdioTransport := transport.NewDefault()

	// Create a server instance
	srv, err := server.NewServer(server.WithLogger(_logger),
		server.WithTransport(stdioTransport),
		server.WithToolDefinitions(func() *iface.ToolDefinitions {
			td := iface.NewToolDefinitions()
			promptTemplate := `{{.ToolPrefix}}: {{.Name}}{{if .Version}}-v{{.Version}}{{end}}：{{.Description}}`

			toolDef := td.Add("time", "Get the current time", "Return the current time in the specified time zone")
			toolDef.AddParameter("timeZone", &iface.ToolParameter{
				Type:        "string",
				Description: "Target time zone, e.g., 'Asia/Shanghai' or 'UTC'",
				Default:     "Asia/Shanghai",
			})

			return td
		}()),
	)
	if err != nil {
		log.Printf("Failed to create server: %v\n", err)
		return
	}
	defer srv.Close()

	// Start the server
	_logger.Logf(ctx, logger.LevelWarn, "Starting Time MCP server")
	if err := srv.Run(ctx); err != nil {
		_logger.Logf(ctx, logger.LevelError, "Server error: %v", err)
		return
	}

	_logger.Logf(ctx, logger.LevelWarn, "Server shutdown completed")
}

✨ Features

• Complete implementation of the MCP protocol in pure Go.
• High-level abstractions for common MCP resources.
• Scalable architecture supporting custom extensions.
• Comprehensive documentation and examples.
• Production-ready with robust error handling.

📦 Installation

MCP4Go requires Go 1.18 or higher. Install using Go modules:

go get github.com/mcp4go/mcp4go

📚 Documentation

MCP4Go provides a complete implementation of the Model Context Protocol, supporting the following features:

• JSON-RPC communication
• Resource lifecycle management
• Prompt engineering design
• Tool definition and invocation
• Sampling parameter settings
• Logging and diagnostics

📄 License

This project is licensed under the MIT License.

💡 How to Contribute

Contributions are welcome! Please refer to our CONTRIBUTING.md for more information.