Several JDWP commands require that a thread be suspended but do not specify an error code if the thread is not suspended:
  MonitorInfo
  Frames
  FrameCount
  OwnedMonitors
  OwnedMonitorsStackDepthInfo

Also, these commands
  ForceEarlyReturn
  PopFrames

require a thread to be suspended, but the error code returned if a thread is not suspended is
   THREAD_NOT_SUSPENDED 13 If the specified thread has not been suspended by an event.


If the thread is suspended by a non-event, eg, a suspend command, either the
description of the command is wrong, or the error code is wrong.