The notify_workers
operation sends an email to one or more Workers that you specify with the Worker ID. You can specify up to 100 Worker IDs to send the same message with a single call to the NotifyWorkers operation. The NotifyWorkers operation will send a notification email to a Worker only if you have previously approved or rejected work from the Worker.
See https://www.paws-r-sdk.com/docs/mturk_notify_workers/ for full documentation.
mturk_notify_workers(Subject, MessageText, WorkerIds)
[required] The subject line of the email message to send. Can include up to 200 characters.
[required] The text of the email message to send. Can include up to 4,096 characters
[required] A list of Worker IDs you wish to notify. You can notify upto 100 Workers at a time.