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MCP Server for WinDbg Crash Analysis

CI Docs PyPI License: MIT Platform: Windows Python 3.10+

A Model Context Protocol server that bridges AI models with WinDbg for crash dump analysis and remote debugging.

Overview

This MCP server integrates with CDB to enable AI models to analyze Windows crash dumps and connect to remote debugging sessions using WinDbg/CDB.

What is this?

An AI-powered tool that bridges LLMs with WinDbg for crash dump analysis and live debugging. Execute debugger commands through natural language queries like "Show me the call stack and explain this access violation".

What This is Not

Not a magical auto-fix solution. It's a Python wrapper around CDB that leverages LLM knowledge to assist with debugging.

Usage Modes

  • Crash Dump Analysis: Examine Windows crash dumps
  • Live Debugging: Connect to remote debugging targets
  • Directory Analysis: Process multiple dumps for patterns

Quick Start

Prerequisites

Tip

In enterprise environments, MCP server usage might be restricted by organizational policies. Check with your IT team about AI tool usage and ensure you have the necessary permissions before proceeding.

Installation

pip install mcp-windbg

Transport Options

The MCP server supports multiple transport protocols:

Transport Description Use Case
stdio (default) Standard input/output Local MCP clients like VS Code, Claude Desktop
streamable-http Streamable HTTP Modern HTTP clients with bidirectional streaming

Starting with Different Transports

Standard I/O (default):

mcp-windbg
# or explicitly
mcp-windbg --transport stdio

Streamable HTTP:

mcp-windbg --transport streamable-http --host 127.0.0.1 --port 8000

Endpoint: http://127.0.0.1:8000/mcp

Command Line Options

--transport {stdio,streamable-http}  Transport protocol (default: stdio)
--host HOST                              HTTP server host (default: 127.0.0.1)
--port PORT                              HTTP server port (default: 8000)
--cdb-path PATH                          Custom path to cdb.exe
--symbols-path PATH                      Custom symbols path
--filter-script PATH                     Python script with process_input/process_output tool text hooks
--timeout SECONDS                        Command timeout (default: 30)
--verbose                                Enable verbose output

Filter Script Hooks

Use --filter-script to load a small Python helper that rewrites tool text only (for example, to redact PII) without seeing the full MCP JSON-RPC envelope:

mcp-windbg --filter-script C:\filters\pii_redaction.py

The script defines process_input and/or process_output callbacks and runs in-process, so treat it as trusted code. See Redact sensitive data for the callback contract and a worked example.

Configuration

mcp-windbg works with any MCP client. Two common setups are below; see the client configuration guide for Claude Desktop, Copilot CLI, HTTP, and from-source.

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"
            }
        }
    }
}

Claude Code - register the server from the command line:

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

Prefer not to install the package? Replace python -m mcp_windbg with uvx --from git+https://github.com/svnscha/mcp-windbg mcp-windbg in either setup to fetch and run the server on demand.

Once configured, restart your MCP client and start debugging:

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

MCP Compatibility

This server implements the Model Context Protocol (MCP), making it compatible with any MCP-enabled client:

The beauty of MCP is that you write the server once, and it works everywhere. Choose your favorite AI assistant!

Tools

Tool Purpose Use Case
list_windbg_dumps List crash dump files Discovery and batch analysis
open_windbg_dump Analyze crash dumps Initial crash dump analysis
close_windbg_dump Cleanup dump sessions Resource management
open_windbg_remote Connect to remote debugging Live debugging sessions
close_windbg_remote Cleanup remote sessions Resource management
run_windbg_cmd Execute WinDbg commands Custom analysis and investigation
send_ctrl_break Break into a running target Interrupt execution during live debugging

Documentation

Documentation

Topic Description
Getting Started Quick setup and first crash dump analysis
Use cases Analyze a dump, debug a remote target, triage many dumps
Command-line options Every CLI flag, transports, and filter hooks
Tools Reference The MCP tools and their parameters
Client configuration VS Code, Claude Desktop, Copilot CLI, pip, and source
Troubleshooting Common issues and solutions

Examples

Crash Dump Analysis

Analyze this heap address with !heap -p -a 0xABCD1234 and check for buffer overflow"

Execute !peb and tell me if there are any environment variables that might affect this crash"

Run .ecxr followed by k and explain the exception's root cause"

Remote Debugging

"Connect to tcp:Port=5005,Server=192.168.0.100 and show me the current thread state"

"Send CTRL+BREAK to the live session, then dump all thread stacks with ~*k"

"Check for timing issues in the thread pool with !runaway and !threads"

"Show me all threads with ~*k and identify which one is causing the hang"

Blog

Read about the development journey: The Future of Crash Analysis: AI Meets WinDbg

Links

Star History

Star History Chart

License

MIT