Messages Read

This event occurs when a message has been read by the contact.

  "event": "messages_read",
  "timestamp" : "2017-12-29T17:26:17.331Z",
  "data" : {
    "channel": {
      "id": "6456078759331238786",
      "type": "whatsapp"
    "contact": {
      "id": "6456078781510718339",
      "phone_number": "15558576309",
      "platform_id": "15558576389",
      "name": "Han Solo"
    "last_read_timestamp": "2017-12-29T17:26:27.346Z"
data.channelobjectChannel where the resides in.
data.contactobjectContact that has read messages delivered.
data.contactobjectCheck Contact for fields description.
last_read_timestampstringIso 8601 Timestamp

All messages that were sent before this timestamp were read. (It doesn't mean "time when the messages were read".)