OpenCliToMcp.Generator 1.0.1

OpenCliToMcp.Generator

C# source generator that automatically generates MCP (Model Context Protocol) server code from OpenCLI tool definitions.

Overview

OpenCliToMcp.Generator is a Roslyn source generator that simplifies the creation of MCP tools by automatically generating the necessary boilerplate code at compile time. It reads OpenCLI JSON definitions and generates strongly-typed C# code for MCP tool implementations.

Installation

dotnet add package OpenCliToMcp.Generator

Usage

1. Add the package reference to your project
2. Create an OpenCLI JSON definition file (e.g., mytool.opencli.json)
3. Add the [OpenCliTool] attribute to your MCP tool class
4. The generator will create the implementation at compile time

Method 1: File in Project Directory

Place the OpenCLI JSON file in your project directory and reference it by filename:

[OpenCliTool("git-tool.opencli.json")]
public partial class GitToolMcp
{
    // Generated code
}

Method 2: Embedded Resource

Include the JSON file as an AdditionalFiles item in your .csproj:

<ItemGroup>
  <AdditionalFiles Include="git-tool.opencli.json" />
</ItemGroup>

Then reference it in your code:

[OpenCliTool("git-tool.opencli.json")]
public partial class GitToolMcp
{
    // Generated code
}

This method is useful when:

• You want explicit control over which files are included
• The JSON file is in a different directory
• You're creating a NuGet package and want to ensure the file is included

Example OpenCLI Definition

{
  "name": "git-tool",
  "description": "Git operations tool",
  "commands": [
    {
      "name": "status",
      "description": "Show the working tree status",
      "parameters": [
        {
          "name": "short",
          "description": "Give the output in short format",
          "type": "boolean"
        }
      ]
    }
  ]
}

Example Usage

using OpenCliToMcp.Core;

[OpenCliTool("git-tool.opencli.json")]
public partial class GitToolMcp
{
    // The generator will create:
    // - Constructor with ICliExecutor dependency
    // - ToolDefinition property
    // - CallToolAsync method implementation
    // - Strongly-typed parameter classes
}

Generated Code

The generator creates:

• MCP tool implementation with proper method signatures
• Parameter validation and parsing
• Type-safe parameter classes
• Integration with OpenCliToMcp.Core for CLI execution

Features

• Compile-time Generation: No runtime overhead
• Type Safety: Strongly-typed parameter classes
• Validation: Built-in parameter validation
• IntelliSense Support: Full IDE support for generated code
• Diagnostics: Helpful error messages during compilation

Analyzer Diagnostics

Requirements

• .NET 6.0 or later (for the target project)
• C# 9.0 or later
• OpenCliToMcp.Core package

License

Licensed under the Apache License, Version 2.0. See LICENSE for details.