What problem does it solve? Adding a new HID command to the PolyKybd keyboard requires coordinated changes across the QMK firmware and the Python host app, and forgetting the protocol version gate causes commands to connect successfully but then NACK at runtime on older keyboards instead of degrading cleanly. ## Core Features & Use Cases - End-to-end checklist: Covers the firmware case NN handler, PROTOCOL_VERSION bump, host FEATURE_MIN_PROTOCOL gate, device/core/RPC/CLI/GUI wiring, and mock mirroring. - Gate and wire-byte testing: Pins payload bytes in command tests and threshold behavior in capability tests, including the unflagged form below the threshold when adding a flag to an existing command. - Landing guidance: Handles both-variant firmware builds, CLAUDE.md protocol documentation, correct bump labels, and coordinated shipping of the two repositories. - Use Case: When asked to let the host set a new device mode on the keyboard, follow the skill to add the gated command, mirror it through the daemon RPC layer, and verify both repos agree on the protocol version. ## Quick Start Ask the assistant to add a new gated HID command to the PolyKybd keyboard, for example to let the host set a new device option, and have it follow the firmware and host checklist end to end.
