Gmail inbox audit logging

auditlog.gs

/**
 * Retrieves all inbox threads and tags them
 * that way, when you accidentally archive something,
 * you can figure out what it was!
 * https://script.google.com/macros/
 */
function auditLogInbox() {
  var threads = GmailApp.getInboxThreads();
  var label = GmailApp.getUserLabelByName("auditlog");
  label.addToThreads(threads);
};