MCP Server for WinDbg Crash Analysis

MCP Server for WinDbg Crash Analysis

A Model Context Protocol server that bridges AI models with WinDbg for crash dump analysis, user-mode remote debugging, and kernel debugging.

[!TIP]

Looking for AI debugging built into WinDbg itself? Microsoft now ships an official

WinDbg MCP, starting with WinDbg 1.2610.1001.0. You enable it in WinDbg's MCP service

settings, and chat with your active debugging session from VS Code with GitHub Copilot or

from the GitHub Copilot CLI. If that is what you want, start there:

- Introducing WinDbg MCP (announcement)

- Set up WinDbg MCP and the overview

- Get the latest WinDbg

This project is an independent, community-built alternative. It runs cdb.exe / kd.exe

headless, so it fits when you want to use another MCP client, drive a debugger from another machine over HTTP, or script triage across many

dumps without opening the WinDbg UI.

Overview

This server drives the Windows debuggers - CDB for user mode (dumps and -remote) and KD for kernel targets (-k) - so you can debug in natural language: *"Show me the call stack and explain this access violation"* or *"Open a kernel session and tell me which driver bugchecked."*

It is not a magical auto-fix. It is a Python wrapper around cdb.exe / kd.exe that lets an LLM run real debugger commands and reason about the output.

Features

• Crash dump analysis - open a .dmp/.mdmp/.hdmp and get automated triage (!analyze -v, stacks, modules, threads) in a single call.
• User-mode remote debugging - attach to a live cdb/WinDbg debug server (-remote) over TCP, a named pipe, or COM, and break in on demand.
• Kernel debugging - attach to a kernel target (-k, driven by kd.exe) over KDNET, a named pipe, or serial; the server waits for the target and breaks in for you.
• Run any WinDbg/KD command - drive an open session with arbitrary commands (kb, !process 0 0, !heap, lm, ...) described in natural language.
• Session ids - every open returns a session id; several sessions (dumps, remote, kernel) can be open at once and are addressed independently.
• Resilient live sessions - per-call timeouts, and a slow live command that outruns its timeout is broken into with CTRL+BREAK and the session resynchronized instead of wedging.
• Multi-dump triage - discover and compare many dumps across a directory.
• Text filter hooks - a --filter-script can redact PII/secrets from tool arguments and output before they leave the machine.
• stdio or HTTP - run locally over stdio, or as a streamable-HTTP service you drive from another machine.

Use cases

Tools

Every open_* tool returns an opaque `session_id` (e.g. cdb-1a2b3c4d); pass it to the matching run_*, close_*, send_ctrl_break, and wait_for_break calls. User-mode targets (dumps and -remote) run under cdb.exe; kernel targets and kernel dumps run under kd.exe.

Parameters, timeouts, and the built-in triage prompts are in the tools reference.

Quick start

[!NOTE]

Claude Code in enterprise environments: when managed settings define allowedMcpServers,

plugin-bundled MCP servers may be silently skipped (Claude Code issue #32882).

I recommend installing and registering the server manually,

then optionally adding the skills or agents plugin.

The server must still be permitted by your organization's MCP policy.

Prerequisites

• Windows with Debugging Tools for Windows or WinDbg from the Microsoft Store, which ship cdb.exe and kd.exe (auto-detected).
• Any MCP-compatible client (Claude Code, GitHub Copilot, Claude Desktop, Cursor, Windsurf, Cline, ...).

Python is not a prerequisite in itself. Each route below states what it needs.

Install in Claude Code

Install the server plugin if needed, then optionally add skills, agents, or both:

Server with uvx

The shortest path: two lines, no pip install, no MCP configuration to edit. Adds the eleven tools, with symbols preconfigured. Skills and agents are installed separately.

/plugin marketplace add svnscha/mcp-windbg

/plugin install mcp-windbg-uvx@mcp-windbg

Needs uv, which supplies uvx: winget install astral-sh.uv. The plugin uses it to fetch the pinned server from PyPI on first use, so there is nothing else to install. See the plugin README for symbols and options.

Registering the server yourself

If you would rather not use the plugin, or you already run the package:

pip install mcp-windbg

claude mcp add mcp-windbg -s user -e _NT_SYMBOL_PATH="SRV*C:\Symbols*https://msdl.microsoft.com/download/symbols" -- python -m mcp_windbg

Needs Python 3.10 or higher. Add either optional plugin below for guided workflows or an agent.

Skills for an existing server

After installing the uvx plugin or registering mcp-windbg yourself, optionally add the four skills:

/plugin marketplace add svnscha/mcp-windbg

/plugin install mcp-windbg-skills@mcp-windbg

Invoke /mcp-windbg-skills:analyze-dump, /mcp-windbg-skills:debug-remote, /mcp-windbg-skills:kernel-debug, or /mcp-windbg-skills:windbg-doctor. This plugin uses your configured MCP connection and adds no server, runtime, symbol settings, or crash-analyst agent. It works with a native executable, Python installation, or HTTP service exposing the mcp-windbg tools. Install this plugin alongside uvx for the server and skills together, or omit it to use just the tools. When upgrading from a version that bundled skills, install this plugin to keep the workflows; their invocation prefix changes from /mcp-windbg: to /mcp-windbg-skills:. The server's built-in MCP prompts remain available independently of these plugins. See the plugin guide for updating or switching plugins.

Agents for an existing server

/plugin marketplace add svnscha/mcp-windbg

/plugin install mcp-windbg-agents@mcp-windbg

Ask: *"Use the mcp-windbg-agents:crash-analyst agent on C:\dumps\app.dmp"*. It investigates the dump and returns a verdict, evidence, and next steps through your existing MCP connection. It requires neither uvx nor the skills plugin. When upgrading from a version that bundled the agent, install this plugin to keep it.

Install without Python

Every release attaches mcp-windbg.exe: one signed executable carrying its own interpreter and every dependency. cdb.exe is still required. Point your client's command at the file and give it no args.

The release also publishes SHA256SUMS, and the binary is code signed, so both are checkable:

(Get-FileHash .\mcp-windbg.exe -Algorithm SHA256).Hash

Get-AuthenticodeSignature .\mcp-windbg.exe | Format-List Status, SignerCertificate

Status should read Valid. The signer is Liasoft GmbH, which sponsors the signing certificate; the project is written by Sven Scharmentke.

Install in another client

pip install mcp-windbg

Needs Python 3.10 or higher. Then point the client at python -m mcp_windbg. For VS Code (GitHub Copilot), press F1 and select MCP: Open User Configuration to enable it in every workspace:

{

"servers": { "mcp_windbg": { "type": "stdio", "command": "python", "args": ["-m", "mcp_windbg"], "env": { "_NT_SYMBOL_PATH": "SRV*C:\\Symbols*https://msdl.microsoft.com/download/symbols" } } } }

See the client configuration guide for Claude Desktop, Copilot CLI, Autohand Code, HTTP, and from-source setups.

Start debugging

Restart your client, then ask for what you want:

Analyze the crash dump at C:\dumps\app.dmp

Connect to tcp:Port=5005,Server=192.168.0.100 and show me the current thread state Open a kernel session on net:port=50000,key=1.2.3.4, run !analyze -v, and tell me which driver bugchecked

Server options (--cdb-path, --kd-path, --symbols-path, --filter-script, --transport, ...) are documented in the [command-line reference](