Google Apps Script for deleting empty spam messages from Gmail

DeleteEmptySpam.gs

function deleteMessageIfEmpty() {
  var threads = GmailApp.search('is:unread in:inbox')

  for (const thread of threads) {
    const messages = thread.getMessages()
    if (messages.length != 1) { continue; }

    const msg = messages[0];
    const words = msg.getPlainBody().trim().split(" ");

    //if (msg.getSubject.length == 0 && msg.getPlainBody().trim().length == 0
    if (words.length < 3 && msg.getBody().length < 256) {
      console.log("Deleting empty spam from: " + msg.getFrom())
      
      const reply = msg.reply("** Address not found **\n\n\
Your message wasn't delivered to " + msg.getTo() + " because the address couldn't be found, \
or is unable to receive mail.\n\nLearn more here: https://support.google.com/mail/?p=3DNoSuchUser\n\n\
The response was:\n\n550 5.1.1 The email account that you tried to reach does not exist. Please \
try double-checking the recipient's email address for typos or unnecessary \
spaces. Learn more at https://support.google.com/mail/?p=3DNoSuchUser m189-\
20020a633fc6000000b003806a0489e6sor8827957pga.40 - gsmtp", {
  subject: "Delivery Status Notification (Failure)",
  name: "Mail Delivery Subsystem",
  replyTo: "mailer-daemon@googlemail.com"
})
    
      msg.moveToTrash()
      reply.moveToTrash()
    }
  }
}