curl --request GET \
  --url http://localhost/api/v3/roles/definitions

{
  "data": [
    {
      "id": 123,
      "name": "<string>",
      "handle": "<string>",
      "description": "<string>",
      "short_description": "<string>",
      "icon": "<string>",
      "image_url": "<string>",
      "timezone": "<string>",
      "period": 123,
      "period_type": "<string>",
      "absolute_expiry": "<string>",
      "group_name": "<string>",
      "group_handle": "<string>",
      "notes": "<string>",
      "meta": [
        "<unknown>"
      ],
      "custom_fields": {},
      "created_at": "<string>",
      "updated_at": "<string>"
    }
  ]
}