curl --request POST \
  --url https://your-instance.example.com/api/messages/quick-bulk-send \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "contactIds": [
    "65c2d0e0f0a0b0c0d0e0f0a0",
    "65c2d0e0f0a0b0c0d0e0f0a1"
  ],
  "message": "Hi {{firstName}}, our team will be in touch shortly."
}
'

{
  "success": true,
  "summary": {
    "total": 2,
    "success": 1,
    "failed": 1
  },
  "results": [
    {
      "contactId": "65c2d0e0f0a0b0c0d0e0f0a0",
      "success": true,
      "name": "Jane Doe",
      "messageId": "SMxxx",
      "messageDocId": "67d0a0b0c0d0e0f0a0b0c0d0",
      "status": "queued"
    },
    {
      "contactId": "65c2d0e0f0a0b0c0d0e0f0a1",
      "success": false,
      "name": "John Smith",
      "error": "Invalid phone number"
    }
  ]
}