Done. The email triggered on a forwarded message from Rohan asking me to log Lance Adams's tool allowance purchase. I found the earlier thread showing I already extracted the invoice details and as...

{
  "labelIds": [
    "UNREAD",
    "IMPORTANT",
    "INBOX"
  ],
  "threadId": "19ea4a6544f5edc3",
  "messageId": "19eb3695a1fbffbf"
}