# mcp-windbg reaches 1.0.0 now with kernel debugging > Source: > Published: 2026-07-17 06:28:17+00:00 First stable release, and the one where kernel debugging actually works. The tool surface is redesigned around opaque **session ids** and split by debugger engine: user-mode (`cdb.exe` ) and kernel (`kd.exe` ). **This is a breaking change** for clients of the 0.x tools. Every `*_windbg_*` tool has a new name, listed under Changed. ### Added **Kernel debugging**-`open_kd_session` ,`run_kd_command` , and`close_kd_session` attach to a kernel target over KDNET (`net:port=,key=` ), a named pipe (`com:pipe,port=\\.\pipe\...` ), or serial, driven by`kd.exe` . This was impossible in 0.x: every remote connection was launched with`-remote` , which is user-mode only, so a kernel target could never connect ([#62](https://github.com/svnscha/mcp-windbg/issues/62),[#47](https://github.com/svnscha/mcp-windbg/issues/47)).**Kernel sessions arrive already stopped**-`open_kd_session` waits for the target's connect banner and breaks in for you, so there is no separate break-in step.**Closing a kernel session sets the machine running again**-`close_kd_session` sends`g` by default (`resume: true` ). Pass`resume: false` only to leave the target halted on purpose.- point the server at a specific`--kd-path` `kd.exe` , the counterpart to`--cdb-path` . Kernel sessions need their own option because`cdb.exe` cannot drive a kernel cable.**Session ids**- every`open_*` returns an opaque`session_id` (`cdb-…` /`kd-…` ) on its first output line, and`run_*` ,`close_*` , and`send_ctrl_break` address a session by that id. The kind is enforced: a`cdb` id passed to`run_kd_command` (or the reverse) returns an error naming the right tool.**Per-call timeouts**-`timeout_seconds` on any`open_*` /`run_*` overrides that tool's default (`open_cdb_dump` 180s, connects 60s,`run_cdb_command` 60s,`run_kd_command` 120s). The server-wide`--timeout` (default 60s) is the floor.- a guided investigation of a live user-mode target: break in,`remote-triage` prompt orient, then track down the hang or crash.- the same for a kernel target, including telling a real bugcheck`kernel-triage` prompt apart from a plain break-in, and releasing the machine at the end. ### Changed **BREAKING**-`list_windbg_dumps` is now`list_dumps` .**BREAKING**-`open_windbg_dump` is now`open_cdb_dump` .**BREAKING**-`open_windbg_remote` is now`open_cdb_remote` .**BREAKING**-`run_windbg_cmd` is now`run_cdb_command` (user mode) or`run_kd_command` (kernel). The`connection_type` discriminator is gone; the tool name says which engine.**BREAKING**-`close_windbg_dump` and`close_windbg_remote` are both now`close_cdb_session` .**BREAKING**-`send_ctrl_break` takes a`session_id` .**BREAKING**- sessions are addressed by id, not by dump path or connection string, and`run_*` no longer opens one implicitly: open a session first. Reopening the same dump gives you an independent session instead of silently reusing one.**Module layout**- kernel sessions live in`kd_session.py` and user-mode in`cdb_session.py` , over a shared`debug_session.py` that owns the subprocess and marker protocol.**Docs**- README and the docs site rewritten around the new tools and the session-id flow, with a "Debug a kernel target" guide, a Development page, and client guides for Claude Code and Autohand Code ([#63](https://github.com/svnscha/mcp-windbg/pull/63)). Setup instructions standardize on`pip install mcp-windbg` and `python -m mcp_windbg` .**Dependencies**- runtime floors refreshed (`mcp>=1.28.1` ,`pydantic>=2.13.4` , `starlette>=1.3.1` ,`uvicorn>=0.51.0` ), plus`pytest>=9.1.1` , and`uv.lock` regenerated. The streamable-http transport was smoke-tested against the Starlette 0.x to 1.x bump. ### Fixed **A slow command no longer wedges a live session.** When a command outruns its timeout the debugger is still busy running it, so the server now breaks in with CTRL+BREAK and resynchronizes before reporting the timeout. The session is usable again for the next command instead of stranded.**A slow command's output is no longer attributed to the next command.** Every command waits on its own unique completion marker, so late output from one command can never be mistaken for the next one's result.**Debugger processes are cleaned up on close.**`cdb.exe` launched through the Microsoft Store execution aliases spawns a child that a plain terminate left behind, still holding the target. Shutdown now does a Windows process-tree kill. ### Removed - All `*_windbg_*` tool names, and the`connection_type` parameter on`run_windbg_cmd` and `send_ctrl_break` , superseded by the`cdb` /`kd` split. - Session reuse by dump path or connection string. `open_*` always creates a fresh session and returns its id. ### Added **Documentation site**: New MkDocs (Material) user guide under`docs/` , deployed to GitHub Pages via`pages.yml` . Covers getting started, the use cases, and a reference for the command-line options, tools, and client configuration. Content migrated and trimmed from the project wiki.**Prompts reference**: Documented the built-in`dump-triage` MCP prompt and its`dump_path` argument (`docs/reference/prompts.md` ).**Usage guide coverage**: New use-case pages for running the server over HTTP (`Debug from another machine` ) and scrubbing tool output (`Redact sensitive data` ), plus WER auto-capture setup in the triage guide and the`dump-triage` prompt in the crash-dump guide. Documented the HTTP transport's lack of authentication, that attach-by-PID is unsupported, and that sessions are concurrent. ### Changed **Package metadata**: Filled in distribution metadata so`pip show` / PyPI are complete - added the author/maintainer email, project URLs (Homepage, Repository, Issues, Changelog), and classifiers for Windows, console environment, and the Debuggers/QA topics ([#36](https://github.com/svnscha/mcp-windbg/issues/36))**Contributor guide**: Migrated`AGENTS.md` to`CLAUDE.md` and added`.claude/rules/` (Markdown typography and documentation authoring), plus`scripts/Format-Docs.ps1` to enforce the typography rules**Docs tooling**: Bumped the docs build dependencies in`requirements-docs.txt` to their latest patch floors -`mkdocs>=1.6.1` ,`mkdocs-material>=9.7.6` ,`pymdown-extensions>=10.21.3` (consolidates[#51](https://github.com/svnscha/mcp-windbg/pull/51),[#52](https://github.com/svnscha/mcp-windbg/pull/52),[#53](https://github.com/svnscha/mcp-windbg/pull/53))**Test suite**: Replaced the ad-hoc tests with a declarative end-to-end harness. Each`tests/scenarios/*.yaml` runs against a really-hosted`python -m mcp_windbg` server driven by a real MCP client (only the LLM is faked). Live scenarios carry`live` /`remote` markers and skip cleanly without CDB, so`-m "not live"` runs anywhere. Adds`pyyaml` as a dev dependency.**Coverage**: The harness hosts the server under`coverage run --parallel-mode` (set`MCP_WINDBG_COVERAGE` ), so coverage reflects the subprocess where tool dispatch runs rather than the test process. The suite reaches 90%+; CI enforces a floor with`coverage report --fail-under=88` (margin below the ~91% actual for cross-version and cdb-output jitter). Code that cannot be line-measured end-to-end (the streamable-http transport on Windows, atexit cleanup, debug-only and defensive branches) is excluded with documented`# pragma: no cover` and`exclude_also` rules. Adds`coverage` as a dev dependency.**LFS dumps are mandatory**: a scenario whose`requires.dump` file is missing now hard-fails (run`git lfs pull` ) instead of skipping, so a half-set-up checkout is a loud error rather than silent green. ### Removed **Dead code**: Removed three unused functions surfaced while raising test coverage -`server.execute_common_analysis_commands` ,`CDBSession.get_session_id` , and`prompts.get_available_prompts` . None had callers. ### Fixed **Stdio server resilience**: The stdio transport no longer crashes on a malformed input line.`serve()` now uses the SDK default`raise_exceptions=False` , so an unparseable line (e.g. when the server is run directly in a terminal) is logged instead of tearing down the whole process ([#45](https://github.com/svnscha/mcp-windbg/issues/45)) ### Added **Tool Content Filter Script Hooks**: Added`--filter-script` so trusted Python helpers can rewrite string-valued tool arguments and tool text output for use cases like PII redaction without exposing full MCP protocol messages ### Added **Live Debugger Break-In**: Added the`send_ctrl_break` tool to interrupt an active CDB/WinDbg session with CTRL+BREAK for dump and remote debugging workflows ([#40](https://github.com/svnscha/mcp-windbg/pull/40)) ### Changed **Dependency Refresh**: Updated runtime dependency floors for`mcp` ,`pydantic` ,`starlette` , and`uvicorn` , and refreshed test and validation tooling versions in`pyproject.toml` **CI Dependency Maintenance**: Updated GitHub Actions dependencies for Python setup and artifact handling in release workflows ([#39](https://github.com/svnscha/mcp-windbg/pull/39),[#42](https://github.com/svnscha/mcp-windbg/pull/42)) ### Fixed **Registry Compatibility**: Restored MCP registry compatibility by reverting`server.json` to the supported`2025-10-17` schema version**Publishing Workflow**: Adjusted MCP publishing workflows to match current registry publisher behavior ### Fixed **Registry Schema Migration**: Updated MCP server schema from deprecated`2025-10-17` to current`2025-12-11` version for mcp-publisher compatibility ### Added **HTTP Transport in Registry**: Added`streamable-http` transport configuration to server.json for MCP registry discovery**Schema Validation in CI**: New`validate-server-schema.py` script validates server.json against the official MCP schema ### Fixed **Registry Schema Update**: Updated MCP server schema version from 2025-09-29 to 2025-10-17 for compatibility with registry.modelcontextprotocol.io**CI Cache Warning**: Disabled unnecessary dependency caching in PyPI publish job to eliminate spurious warnings ### Added **HTTP Transport Support**: New`--transport streamable-http` option enables HTTP-based communication alongside the default stdio transport ([#31](https://github.com/svnscha/mcp-windbg/issues/31))**MCP Prompt API**: Implemented prompt templates for AI-assisted crash dump triage and analysis ([#25](https://github.com/svnscha/mcp-windbg/issues/25)) ### Changed **Updated Dependencies**: Bumped`mcp` to 1.17.0,`pydantic` to 2.12.0, and other dependencies ([#26](https://github.com/svnscha/mcp-windbg/issues/26))**Improved Prompt Templates**: Removed hard-coded model references from prompt templates for better flexibility ([#29](https://github.com/svnscha/mcp-windbg/issues/29))**Updated Dependabot Configuration**: Improved automated dependency update settings ### Fixed **Session Cleanup**: Prevent stale debugging sessions if`.shutdown()` fails ([#28](https://github.com/svnscha/mcp-windbg/issues/28)) **What's New in This Release** This release focuses on making mcp-windbg more reliable, faster, and easier to use for everyone - from beginners to advanced users. ### New Features **Core** - Live debugging session support via `open_windbg_remote` and`close_windbg_remote` - Extended dump file support for `.mdmp` and`.hdmp` formats - Microsoft Store WinDbg CDB compatibility **Devops** - Set up continuous integration that automatically tests the code with Python versions 3.10 through 3.14 - Added automatic dependency updates to keep everything secure and up-to-date - Streamlined the release process so new versions reach users faster **Development** - Switched to `uv` - a lightning-fast Python package manager that's 10-100x faster than pip - Development setup is now much quicker with commands like `uv sync` and`uv run` - More reliable builds with locked dependency versions **Documentation** - Added comprehensive debugging instructions for AI assistants ( )`AGENTS.md` - Created structured templates to help analyze crash dumps more effectively ( )`.github/prompts/dump-triage.prompt.md` - All documentation is now available in the [repository Wiki](https://github.com/svnscha/mcp-windbg/wiki)for easy access - Simplified the main to focus on getting started quickly`README.md` - Added this structured to track all project changes`CHANGELOG.md` ### Improvements **Performance Boost**: Build times are significantly faster thanks to the new tooling **Enhanced Security**: Automatic scanning and updates keep dependencies secure ### Community Contributions Special thanks to [@sooknarine](https://github.com/sooknarine) for these valuable contributions: - [Find local dumps with other common extensions #6](https://github.com/svnscha/mcp-windbg/pull/6)- Now finds more crash dump files automatically - [Add support for remote debugging #10](https://github.com/svnscha/mcp-windbg/pull/10)- Connect to live debugging sessions - Initial version as blogged about.