A JetBrains IDE plugin that exposes an MCP (Model Context Protocol) server, giving AI coding assistants full programmatic control over the debugger. Set breakpoints, step through code, inspect variables, and evaluate expressions—all driven autonomously by your AI assistant.

Works with all JetBrains IDEs: IntelliJ IDEA, PyCharm, WebStorm, GoLand, PhpStorm, RubyMine, CLion, Rider, and Android Studio.

Debugger MCP Server gives AI coding assistants complete control over the IDE's debugger through the Model Context Protocol (MCP). Let your AI assistant debug code autonomously—from setting breakpoints to inspecting variables to stepping through execution.

Debug Session Management

• Start/Stop Sessions - Launch any run configuration in debug mode
• Rich Status - Get comprehensive state in a single call (variables, stack, source context)
• Multi-Session Support - Manage multiple concurrent debug sessions

Breakpoint Management

• Line Breakpoints - Set breakpoints at any valid location
• Conditional Breakpoints - Add conditions that must be true to pause
• Tracepoints - Log messages without pausing execution

Execution Control

• Step Over/Into/Out - Navigate through code line by line
• Resume & Pause - Control execution flow
• Run to Line - Continue execution until a specific line

Variable Inspection

• View Variables - Inspect local variables, arguments, and object fields
• Modify Values - Change variable values during debugging

Expression Evaluation

• Evaluate Expressions - Run arbitrary expressions in the current context
• Code Fragments - Execute multi-line code snippets

Stack & Thread Navigation

• Stack Traces - View the complete call stack with source locations
• Frame Selection - Switch context to any stack frame
• Thread Listing - See all threads and their states

Unlike manual debugging, this plugin enables:

• Autonomous AI Debugging - Your AI assistant can debug code without human intervention
• Rich Context in Single Calls - Get variables, stack, and source in one request
• Programmatic Breakpoint Control - Set conditional breakpoints with complex expressions
• Cross-IDE Compatibility - Works with any JetBrains IDE that supports XDebugger
• 22 Comprehensive Tools - Full debugging capability through MCP

Perfect for AI-assisted development workflows where you want your assistant to investigate bugs, validate fixes, or explore code behavior autonomously.

• Installation
• Quick Start
• Client Configuration
• Available Tools
• Multi-Project Support
• Tool Window
• Error Codes
• Settings
• Requirements
• Contributing

Settings/Preferences > Plugins > Marketplace > Search for "Debugger MCP Server" > Install

Go to JetBrains Marketplace and install it by clicking the Install to ... button.

Download the latest release and install it manually: Settings/Preferences > Plugins > ⚙️ > Install plugin from disk...

1. Install the plugin and restart your JetBrains IDE
2. Open a project - the MCP server starts automatically
3. Find your IDE port: Settings > Build, Execution, Deployment > Debugger > Built-in Server Port (default: 63342)
4. Configure your AI assistant with the server URL: http://127.0.0.1:{PORT}/debugger-mcp/sse
5. Use the tool window (bottom panel: "Debugger MCP Server") to copy configuration or monitor commands

The easiest way to configure your AI assistant:

1. Open the "Debugger MCP Server" tool window (bottom panel)
2. Click the prominent "Install on Coding Agents" button on the right side of the toolbar
3. A popup appears with two sections:
   • Install Now - For Claude Code CLI and Codex CLI: Runs the installation command automatically
   • Copy Configuration - For other clients: Copies the JSON config to your clipboard
4. For "Copy Configuration" clients, paste the config into the appropriate config file

Just tell your AI assistant:

"Debug the calculateTotal function—set a breakpoint at line 42, run the tests in debug mode, and show me the variable values when it pauses."

Or for more complex debugging:

"There's a bug in UserService. Set a breakpoint at line 42, run the tests in debug mode, and when it breaks, show me the stack trace and all local variables."

The easiest way is to use the "Install on Coding Agents" button in the IDE's tool window—it generates the correct command with your IDE-specific server name (e.g., intellij-debugger, pycharm-debugger).

Or run this command manually in your terminal (replace <ide>-debugger with your IDE name):

claude mcp add --transport sse intellij-debugger http://127.0.0.1:63342/debugger-mcp/sse --scope user

IDE-specific server names:

• IntelliJ IDEA: intellij-debugger
• PyCharm: pycharm-debugger
• WebStorm: webstorm-debugger
• GoLand: goland-debugger
• PhpStorm: phpstorm-debugger
• RubyMine: rubymine-debugger
• CLion: clion-debugger
• RustRover: rustrover-debugger
• Android Studio: android-studio-debugger

Options:

• --scope user - Adds globally for all projects
• --scope project - Adds to current project only

To remove: claude mcp remove intellij-debugger (use your IDE's name)

The easiest way is to use the "Install on Coding Agents" button in the IDE's tool window—it generates the correct command with your IDE-specific server name (e.g., intellij-debugger, pycharm-debugger).

Or run this command manually in your terminal (replace <ide>-debugger with your IDE name):

codex mcp add intellij-debugger -- npx -y mcp-remote http://127.0.0.1:63342/debugger-mcp/sse --allow-http

To remove: codex mcp remove intellij-debugger (use your IDE's name)

Add to .cursor/mcp.json in your project root or ~/.cursor/mcp.json globally:

{
  "mcpServers": {
    "intellij-debugger": {
      "url": "http://127.0.0.1:63342/debugger-mcp/sse"
    }
  }
}

Add to ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "intellij-debugger": {
      "serverUrl": "http://127.0.0.1:63342/debugger-mcp/sse"
    }
  }
}

{
  "mcp.servers": {
    "intellij-debugger": {
      "transport": "sse",
      "url": "http://127.0.0.1:63342/debugger-mcp/sse"
    }
  }
}

Note: Replace intellij-debugger with your IDE's server name (see list above).

Note: Replace 63342 with your actual IDE port if different. Check Settings > Debugger > Built-in Server Port.

The plugin provides 22 MCP tools organized by category:

Note: For detailed tool documentation with parameters, examples, and response formats, see USAGE.md.

When multiple projects are open in a single IDE window, you must specify which project to use with the project_path parameter:

{
  "name": "set_breakpoint",
  "arguments": {
    "project_path": "/Users/dev/myproject",
    "file_path": "/Users/dev/myproject/src/Main.java",
    "line": 42
  }
}

If project_path is omitted:

• Single project open: That project is used automatically
• Multiple projects open: An error is returned with the list of available projects

The plugin adds a "Debugger MCP Server" tool window (bottom panel) that shows:

• Server Status: Running indicator with server URL and port
• Project Name: Currently active project
• Command History: Log of all MCP tool calls with:
  • Timestamp
  • Tool name
  • Status (Success/Error/Pending)
  • Parameters and results (expandable)
  • Execution duration

Configure the plugin at Settings > Tools > Debugger MCP Server:

• JetBrains IDE 2025.1 or later (any IDE based on IntelliJ Platform)
• JVM 21 or later
• MCP Protocol 2024-11-05

All JetBrains IDEs with XDebugger support:

The plugin supports dual MCP transports on the IDE's built-in web server:

AI Assistant ──────► GET /debugger-mcp/sse           (establish SSE stream)
                     ◄── event: endpoint             (receive POST URL with sessionId)
             ──────► POST /debugger-mcp?sessionId=x  (JSON-RPC requests)
                     ◄── HTTP 202 Accepted
                     ◄── event: message              (JSON-RPC response via SSE)

AI Assistant ──────► POST /debugger-mcp              (JSON-RPC requests)
                     ◄── JSON-RPC response           (immediate HTTP response)

This dual approach:

• MCP Inspector compatible - Full SSE transport per MCP spec (2024-11-05)
• Claude Code compatible - Streamable HTTP for simple request/response
• Requires no additional ports or processes
• Works with any MCP-compatible client
• Automatically adapts to the IDE's server port

Contributions are welcome! Please:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Run tests: ./gradlew test
5. Submit a pull request

# Build the plugin
./gradlew build

# Run IDE with plugin installed
./gradlew runIde

# Run tests
./gradlew test

# Run plugin verification
./gradlew runPluginVerifier

This project is licensed under the MIT License - see the LICENSE file for details.

Plugin based on the IntelliJ Platform Plugin Template.