Feature guide · native runtime
Keep the transport quiet and recoverable.
A C++ desktop bridge owns Windows desktop handles, and a console-free C++ supervisor keeps the MCP child available with bounded restart.
Behavior
The in-process DLL creates and reopens named desktops, launches children with CREATE_NO_WINDOW, and waits for GUI readiness where applicable. The supervisor proxies stdio byte-for-byte and restarts an unexpectedly terminated Python child with bounded backoff. lowlevel-computer-use-cheap remains an independent direct route.
Configuration
Run scripts/build-native.ps1 to build both components. Client registration prefers the packaged supervisor and falls back to pythonw.exe when it is absent.
Failure modes
- A missing or incompatible DLL selects the Python implementation and reports the exact reason.
- Repeated child termination is capped at five restarts in 60 seconds.
- Parent stdin EOF reaches the child for normal shutdown.
Security
The native components add neither privileges nor a sandbox. They use no shell, create no console, and never write protocol payloads to logs or files.
Verification
The Windows suite covers ABI loading, exact stdio forwarding, fallback selection, desktop create/reopen/launch/close, invalid-name refusal, and packaged wheel contents.