curl --request POST \
  --url https://api.comm.com/api/v1/segments/summary \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "segment_ids": [
    "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  ]
}
'

{
  "data": {
    "contacts_total": 123,
    "contacts_left": 123,
    "avg_sms_per_contact": 123,
    "countries_breakdown": [
      "<string>"
    ]
  }
}