curl --request POST \
  --url https://{baseurl}/api/v1/management/attribute-classes \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <x-api-key>' \
  --data '
{
  "environmentId": "{{environmentId}}",
  "key": "my-custom-attribute",
  "name": "My new Attribute",
  "type": "custom"
}
'

{
  "data": {
    "archived": false,
    "createdAt": "2024-04-23T11:21:38.155Z",
    "description": null,
    "environmentId": "clurwouax000azffxt7n5unn3",
    "id": "clvcapx7v0000xz1zskcgf5k0",
    "key": "my-custom-attribute",
    "name": "My new Attribute",
    "type": "custom",
    "updatedAt": "2024-04-23T11:21:38.155Z"
  }
}