message FailControlMessage {
  enum Command {
    // Minions may send these:
    NEED_WORK = 0;	// server replies with WORK_FOLLOWS or DIE
    RESULT_FOLLOWS = 1;	// followed by experiment-specific ExperimentData message (holding both original parameters and experiment result)

    // JobServer may send these:
    WORK_FOLLOWS = 6;	// followed by experiment-specific ExperimentData message
    COME_AGAIN = 7;	// no experiment-specific ExperimentData at the moment, but Campaign is not over yet
    DIE = 8;		// tells the client to terminate
  }

  required Command command = 1;
  repeated uint32 workloadID = 2;
  // identifying the client/server build (e.g., build time in unixtime format)
  required uint64 build_id = 3;
  // campaign server run ID: prevents old clients talking to new servers
  optional uint64 run_id = 4;
  optional uint32 job_size = 5;
}