curl --request POST \
  --url https://api.criteo.com/preview/retail-media/accounts/{account-id}/audience-segments/estimate-size \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "data": {
    "type": "<string>"
  }
}
'

{
  "data": {
    "attributes": {
      "relativeSize": 123,
      "size": 123
    },
    "type": "<string>"
  },
  "errors": [
    {
      "code": "<string>",
      "detail": "<string>",
      "instance": "<string>",
      "source": {},
      "stackTrace": "<string>",
      "title": "<string>",
      "traceId": "<string>",
      "traceIdentifier": "<string>"
    }
  ],
  "warnings": [
    {
      "code": "<string>",
      "detail": "<string>",
      "instance": "<string>",
      "source": {},
      "stackTrace": "<string>",
      "title": "<string>",
      "traceId": "<string>",
      "traceIdentifier": "<string>"
    }
  ]
}