Mark a thread as read

Records that a user has read up to a specific message in the thread. Unread indicators and badge counts are cleared up to the specified message.

You must supply exactly one of last_read_message or use_latest_message. Omitting both returns 400. If use_latest_message is true and the thread has no messages, the request succeeds silently with no state change.

For server-to-server (S2S) requests where no user identity is present in the token, the user param is required to identify whose read state to update.

{
  "last_read_message": "string",
  "use_latest_message": true,
  "user": "string"
}