MCP Server Developer Tool

🚀 Modular MCP Server

This is a Go implementation of a Model Context Protocol (MCP) server using the github.com/metoro-io/mcp-golang library, refactored in a modular way.

🚀 Quick Start

Project Structure

mcp-server/
├── cmd/
│   └── mcp-server/
│       └── main.go           # Entry point
├── internal/
│   ├── config/
│   │   └── config.go         # Server configuration
│   ├── server/
│   │   ├── server.go         # MCP server implementation
│   │   └── server_test.go    # Server tests
│   ├── tools/
│   │   ├── tool.go           # Tool interface
│   │   ├── execute.go        # Tool to execute shell commands
│   │   ├── showfile.go       # Tool to display files
│   │   ├── searchfile.go     # Tool to search in files
│   │   └── writefile.go      # Tool to write to files
│   └── utils/
│       └── response.go       # Utility for responses
├── go.mod
├── go.sum
└── README.md

Build and Run

# Build the server
cd cmd/mcp-server
go build -o mcp-server

# Run the server
./mcp-server

✨ Features

Security Features

The server now includes a path restriction feature to limit file operations to specified directories.

Configure Allowed Paths

You can configure the allowed paths in the following ways:

1. Use Command-line Flags

# Only allow operations in specific directories
./mcp-server --paths=/home/user/safe:/tmp/workspace

# Explicitly deny certain paths even within the allowed paths
./mcp-server --paths=/home/user --deny-paths=/home/user/.ssh:/home/user/credentials

2. Use Environment Variables

# Set allowed paths
export MCP_ALLOWED_PATHS=/home/user/safe:/tmp/workspace

# Set denied paths
export MCP_DENIED_PATHS=/home/user/.ssh:/home/user/credentials

# Run the server
./mcp-server

3. Programmatic Configuration

You can also create a custom configuration:

cfg := config.DefaultConfig()
cfg.AddAllowedPath("/path/to/allow")
cfg.AddDeniedPath("/path/to/deny")

server, err := server.NewServerWithConfig(cfg)

Default Behavior

• If no paths are specified, the server only allows the current working directory by default.
• Common sensitive directories (e.g., .git and .env) are automatically added to the deny list.

Shell Command Security

For the execute_shell_command tool:

• Commands are restricted to a whitelist of common utilities.
• Custom executable paths must pass the allowed path configuration check.
• The working directory must be within the allowed paths.

💻 Usage Examples

Add New Tools

To add a new tool, follow these steps:

1. Create a new Go file in the internal/tools/ directory.
2. Implement the Tool interface (defined in tool.go).
3. Register the tool with the server, usually in server.go.

For example, to add a new tool:

// new_tool.go
package tools

import (
	"internal/tools"
)

type NewTool struct{}

func (n *NewTool) Execute(args []string) error {
    // Implement specific execution logic
    return nil
}

func init() {
	tools.Register("new_tool", &NewTool{})
}

Test the Server

To test the server, run the following command:

# Run tests
go test -v ./...