AdoPrHelperMcp 0.4.0

Azure DevOps PR Helper MCP Server (.NET 8)

A Model Context Protocol (MCP) server for Azure DevOps Pull Request operations, implemented in .NET 8.

Features

• Fetch PR Changes: Downloads all changed files from a PR and saves them to disk with escaped paths and a comprehensive manifest
• Post Comments: Post review comments to PR threads at specific file locations with severity levels
• Authentication: Support for both interactive OAuth and Personal Access Token (PAT) authentication

Prerequisites

• .NET 8 SDK or later
• Azure DevOps account
• An MCP-compatible AI client (GitHub Copilot, Claude Desktop, etc.)

Installation

Build from Source

cd AdoPrHelperMcp
dotnet build
dotnet publish -c Release -o publish

Configuration

For Personal Access Token (PAT) Authentication

1. Create a PAT in Azure DevOps with Code (Read) and Code (Status) permissions
2. Set the environment variable:

   export AZURE_DEVOPS_PAT="your-pat-token"
   

For Interactive OAuth Authentication

No additional configuration needed - the browser will open for authentication.

Usage

Command Line Options

# Run with interactive authentication (default)
dotnet run

# Run with PAT authentication
dotnet run -- --authentication pat
dotnet run -- -a pat

# Show help
dotnet run -- --help

MCP Server Configuration

For GitHub Copilot in VS Code

Add to your VS Code settings.json:

{
  "github.copilot.chat.mcp.servers": {
    "adopr-helper-dotnet": {
      "command": "dotnet",
      "args": ["run", "--project", "path/to/AdoPrHelperMcp/AdoPrHelperMcp.csproj"],
      "env": {
        "AZURE_DEVOPS_PAT": "your-pat-here"  // Optional, for PAT auth
      }
    }
  }
}

For Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "adopr-helper-dotnet": {
      "command": "dotnet",
      "args": ["run", "--project", "path/to/AdoPrHelperMcp/AdoPrHelperMcp.csproj"],
      "env": {
        "AZURE_DEVOPS_PAT": "your-pat-here"  // Optional, for PAT auth
      }
    }
  }
}

Available Tools

azure_devops_fetch_pr_changes

Fetches all changed files from a pull request and saves them directly to a local folder. This prevents context overflow by keeping file contents out of the agent's context.

Parameters:

• pr_url (string, required): The full URL of the Azure DevOps pull request
• output_folder (string, required): Local folder path where files will be saved

What it does:

1. Fetches PR metadata (title, author, branches, timestamps)
2. Gets list of all changed files with diffs
3. For each file:
   • Escapes the file path using ~~~ separator (e.g., src/services/UserService.cs → src~~~services~~~UserService.cs)
   • Writes full file content to {escaped_name}
   • Writes diff to {escaped_name}.diff
4. Creates manifest.json with comprehensive metadata
5. Returns small summary (NOT file contents)

Output Structure:

output_folder/
├── manifest.json                             # Metadata
├── src~~~services~~~UserService.cs           # Full file
├── src~~~services~~~UserService.cs.diff      # Diff
└── ...

Response (small, keeps context clean):

{
  "success": true,
  "manifestPath": "{output_folder}/manifest.json",
  "filesSaved": 15,
  "totalBytes": 52000,
  "summary": {
    "added": 3,
    "modified": 10,
    "deleted": 2,
    "renamed": 0
  }
}

Example:

Fetch changes from https://dev.azure.com/myorg/myproject/_git/myrepo/pullrequest/123 and save to ./pr-changes

azure_devops_post_comment

Posts a review comment to a specific file and line in an Azure DevOps pull request.

Parameters:

• pr_url (string, required): The full URL of the Azure DevOps pull request
• file_path (string, required): File path to attach comment to
• line_number (number, required): Line number to attach comment to
• comment_text (string, required): The comment text to post
• severity (string, optional): Severity level - Critical, High, Medium, Low
• thread_status (string, optional): Thread status - active, fixed, wontFix, closed

Severity Levels:

• Critical - Security vulnerabilities, data loss risks
• High - Bugs, logic errors, potential crashes
• Medium - Code quality, performance issues
• Low - Best practice suggestions, minor improvements

Example:

Post comment "Potential SQL injection vulnerability" to line 42 of src/UserService.cs with severity "Critical"

Recommended Comment Format:

**[Critical]** SQL Injection Vulnerability

The query uses string interpolation which is vulnerable to SQL injection attacks.

**Suggestion:**
Use parameterized queries instead.

**Reference:** .NET Security Guidelines - SQL Injection

Error Handling

All tools return standardized error responses:

{
  "success": false,
  "error": {
    "code": "PR_NOT_FOUND",
    "message": "Pull request not found or access denied"
  }
}

Error Codes:

• PR_NOT_FOUND - PR doesn't exist or no access
• AUTH_FAILED - Authentication failed
• RATE_LIMITED - Too many requests
• FILE_NOT_FOUND - File doesn't exist in PR
• COMMENT_FAILED - Failed to post comment
• INVALID_INPUT - Invalid input parameters
• UNKNOWN_ERROR - Unexpected error

Manifest Structure

The manifest.json file contains comprehensive metadata about the PR:

{
  "prUrl": "https://dev.azure.com/org/project/_git/repo/pullrequest/123",
  "prId": 123,
  "prTitle": "Add user authentication",
  "prDescription": "Implements JWT-based auth...",
  "prAuthor": {
    "displayName": "John Doe",
    "email": "john.doe@example.com"
  },
  "prStatus": "active",
  "sourceBranch": "feature/auth",
  "targetBranch": "main",
  "createdDate": "2026-01-20T10:30:00Z",
  "fetchTimestamp": "2026-01-22T08:40:00Z",
  "statistics": {
    "totalFiles": 15,
    "totalSizeBytes": 52000,
    "changes": {
      "added": 3,
      "modified": 10,
      "deleted": 2,
      "renamed": 0
    }
  },
  "files": [
    {
      "originalPath": "src/services/UserService.cs",
      "escapedName": "src~~~services~~~UserService.cs",
      "diffName": "src~~~services~~~UserService.cs.diff",
      "changeType": "modified",
      "sizeBytes": 4523,
      "diffSizeBytes": 892,
      "linesAdded": 45,
      "linesDeleted": 12
    }
  ]
}

Architecture

The project follows a clean architecture with the following structure:

AdoPrHelperMcp/
├── Models/              # Data models and DTOs
│   ├── AuthOptions.cs
│   ├── PrInfo.cs
│   ├── PullRequest.cs
│   ├── GitModels.cs
│   ├── PrCommentModels.cs
│   ├── ManifestModels.cs
│   └── ErrorModels.cs
├── Auth/                # Authentication services
│   └── Authenticator.cs
├── Services/            # Business logic
│   ├── AzureDevOpsHelper.cs
│   └── PathUtils.cs
├── Mcp/                 # MCP server configuration
│   └── McpTools.cs
└── Program.cs           # Application entry point

Project Structure

• Models: Record types for Azure DevOps API models and MCP responses
• Auth: OAuth and PAT authentication implementations using MSAL
• Services: Azure DevOps REST API integration and utility functions
• Mcp: MCP server tool definitions and handlers

Dependencies

• ModelContextProtocol (0.4.0-preview.3): MCP SDK for .NET
• Microsoft.Identity.Client (4.78.0): MSAL for OAuth authentication
• DiffPlex (1.9.0): Unified diff generation
• System.CommandLine (2.0.0-rc): Command-line argument parsing

Development

Running Tests

dotnet test

Building for Production

dotnet publish -c Release -r win-x64 --self-contained
dotnet publish -c Release -r linux-x64 --self-contained
dotnet publish -c Release -r osx-x64 --self-contained

License

MIT

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Troubleshooting

Authentication Issues

• PAT: Ensure AZURE_DEVOPS_PAT environment variable is set correctly
• OAuth: Check that browser can open and you can authenticate

Connection Issues

• Verify Azure DevOps URL format is correct
• Check network connectivity to Azure DevOps
• Ensure PAT has required permissions

File System Issues

• Ensure the output_folder path is writable
• Check disk space before fetching large PRs
• Path escaping uses ~~~ to avoid file system conflicts

Support

For issues and questions:

• Create an issue on the GitHub repository
• Check Azure DevOps API documentation: https://learn.microsoft.com/en-us/rest/api/azure/devops/

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Converted from TypeScript MCP server at: https://github.com/cuteribs/adopr-helper-mcp