中文版

JDB-MCP 是一款基于 Java 调试接口（JDI）的模型上下文协议（MCP）服务器。它使 AI 代理（如 Claude、Cline、Trae）能够对 Java 应用进行深度运行时调试。

演示

主要能力

• 多传输支持：支持stdio（标准VSCode集成）和http（用于远程/卷调调试）。
• 全功能调试（仅附加模式）：
• 附加到正在运行的进程（debug_attach）——支持任何启用JDWP的Java应用程序（如SpringBoot、Maven、Gradle等）。
• 断点管理（debug_set_breakpoint，debug_set_watchpoint）
• 流量控制（跨步、步入、步出、恢复）
• 状态检测（堆栈跟踪检测，深度结构化变量遍历）
• 线程和类别检查（debug_list_threads，debug_list_classes）
• 动态修改（运行时更改变量值）
• 简化设计：目前专注于单会话调试，消除复杂的sessionId管理需求。
• 需要手动调试模式：目标Java应用程序必须手动启动并启用JDWP选项。

JDB-MCP: Java Debugger MCP Server

中文版

JDB-MCP is a Model Context Protocol (MCP) server based on the Java Debug Interface (JDI). It enables AI agents (such as Claude, Cline, Trae) to perform deep runtime debugging of Java applications.

Demo

Key Capabilities

• Multi-transport Support: Supports both stdio (standard VSCode integration) and http (for remote/curl debugging).
• Full-featured Debugging (Attach Mode Only):
  • Attach to running processes (debug_attach) - Supports any Java application (SpringBoot, Maven, Gradle, etc.) with JDWP enabled.
  • Breakpoint management (debug_set_breakpoint, debug_set_watchpoint)
  • Flow control (Step Over, Step Into, Step Out, Resume)
  • State inspection (Stack trace inspection, deep structured variable traversal)
  • Thread & Class inspection (debug_list_threads, debug_list_classes)
  • Dynamic modification (Change variable values at runtime)
• Simplified Design: Currently focused on single-session debugging, eliminating the need for complex sessionId management.
• Manual Debug Mode Required: The target Java application must be started manually with JDWP options enabled.
• Real-time Awareness: Leveraging MCP Notifications, AI agents are immediately notified when a breakpoint is hit.

Installation & Build

Prerequisites

• JDK 17+ (with JDI module)

Build fatJAR

# Build all modules and generate JARs in the `release/` directory
mvn clean package

# Or build for a specific JDK version:

# For JDK 17+ (Recommended)
mvn clean package -pl jdb-mcp-jdk17 -am

# For JDK 7 (Legacy Support)
mvn clean package -pl jdb-mcp-jdk7 -am

The executable JARs will be located in the release/ directory:

• release/jdb-mcp.jar (JDK 17+)
• release/jdb-mcp-jdk7.jar (JDK 7)

Configuration & Usage

Startup Options

• --transport : Set transport mode (default: stdio).
• --notifications : Enable real-time AI notifications (default: true).

For detailed tool parameter analysis, please refer to the Parameter Guide.

Usage in VSCode (Cline/Claude Dev)

Add the following configuration to your MCP settings:

{
  "mcpServers": {
    "jdb-debugger": {
      "command": "java",
      "args": [
        "-jar",
        "path/to/jdb-mcp.jar"
      ]
    }
  }
}

How to Debug (Attach Mode)

Important: You must manually start your target Java application with JDWP enabled.

1. Start your project:

   java -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=*:5005 -jar your-app.jar
   

2. In the AI chat, request: Attach to localhost:5005 and debug...

Tool List

• debug_attach: Attach to an existing debug port via Socket.
• debug_list_threads: List all threads and their status.
• debug_list_classes: List loaded classes with optional filtering.