{
  doc: {
    _ts: ISODate("2023-01-01T00:00:00Z"),
    _stream_meta: {
       source.offset: 42,      // kafka offset/partition info
       source.partition: 1,
       ...
    },
    a: 1
  },
  errInfo: {
     reason: "Input document arrived late."
  },
  processorName: "foo123"   // processor name that originated this message
  instanceName: "mySP01".   // instance name that originated this message
  // Other fields for the specific error. The missedWindowStartTimes is an example for late arriving documents.
  missedWindowStartTimes: [ISODate("2023-01-01T00:00:00Z")] 
}