curl --request GET \
  --url https://http.us.breakcold.com/api/v1/messages/{messageId} \
  --header 'Authorization: Bearer <token>'

{
  "message": {
    "id": "<string>",
    "workspaceId": "<string>",
    "conversationId": "<string>",
    "sentAtMs": 123,
    "textPlain": "<string>",
    "textHtml": "<string>",
    "subject": "<string>",
    "receivedAtMs": 123,
    "attachmentCount": 123
  }
}