# Git Stuff Server
This repository contains a Node.js application that acts as an MCP (Model Context Protocol) server to provide Git-related functionalities. Currently, it offers a tool to generate the diff for a Git merge commit against its first parent.
## Features
* **MCP Server:** Runs as a standard MCP server using stdio for communication.
* **`get_git_merge_diff` Tool:**
* Accepts a Git merge commit hash.
* Executes the [`GenerateMergeDiff.ps1`](GenerateMergeDiff.ps1) PowerShell script.
* Returns the textual diff content generated by `git show -m --first-parent <commitHash>`.
## Prerequisites
* [Node.js](https://nodejs.org/) (Version supporting ES Modules, check `engines` in [package.json](package.json) if specified, otherwise check `tsconfig.json` target - ES2022)
* [npm](https://www.npmjs.com/) (usually comes with Node.js)
* [Git](https://git-scm.com/) installed and accessible in the system's PATH.
* [PowerShell](https://learn.microsoft.com/en-us/powershell/scripting/install/installing-powershell) (Windows) or `pwsh` (Linux/macOS) installed and accessible in the system's PATH.
## Installation
1. Clone the repository:
```sh
git clone <your-repo-url>
cd GitStuffServer
```
2. Install dependencies:
```sh
npm install
```
## Usage
1. **Build the TypeScript code:**
```sh
npm run build
```
This compiles the TypeScript code from `src/` to JavaScript in `build/`.
2. **Run the server:**
* To run the compiled code:
```sh
npm start
```
* To build and run in development mode:
```sh
npm run dev
```
The server will start and listen for MCP requests on standard input/output.
### Using the `get_git_merge_diff` Tool
When connected via an MCP client, you can call the `get_git_merge_diff` tool with the following input:
* `commitHash` (string): The Git commit hash (SHA) of the merge commit you want to diff.
The tool will return the diff content as text.
## How it Works
1. The MCP server ([`src/index.ts`](src/index.ts)) receives a request for the `get_git_merge_diff` tool.
2. It validates the `commitHash` input.
3. It executes the [`GenerateMergeDiff.ps1`](GenerateMergeDiff.ps1) PowerShell script, passing the `commitHash`.
4. The PowerShell script runs `git show -m --first-parent <commitHash>` and saves the output (including any errors) to a temporary file named `merge_changes.diff` in the server's current working directory.
5. The Node.js server reads the content of `merge_changes.diff`.
6. The server deletes the temporary `merge_changes.diff` file.
7. The server returns the diff content (or an error message) to the MCP client.
## Configuration
Key configuration points are defined as constants within [`src/index.ts`](src/index.ts):
* `SERVER_NAME`: The name registered by the MCP server.
* `SCRIPT_NAME`: The filename of the PowerShell script to execute.
* `OUTPUT_DIFF_FILE`: The name of the temporary diff file created by the script.
## License
This project is licensed under the MIT License - see the [package.json](package.json) file for details.
