# Implementation scope and limitations

A method's presence in the common interface does not mean the corresponding MG400 operation is implemented. Unsupported operations are designed to raise `NotImplementedError`.

- `take_arm()` / `give_arm()`: logical operations, not hardware ownership.
- `halt()` / `stop()`: unsupported because equivalence to the common interface's stop sequence is not established.
- `hand_stop()`: unimplemented without a specified gripper and I/O mapping.
- `drive()`: partially implemented; `path_blend` and J5/J6 have limitations.
- `rotate()`: plane/angle/center trajectory conversion is unimplemented.
- `autocal()`: MG400 automatic calibration is unimplemented.
- `RobotVarManager`: local JSON variable management, not robot-controller variables.

Do not use `halt()` or `stop()` as substitutes for a physical safety stop.