curl --request GET \
  --url https://api.hubapi.com/crm/v3/property-validations/{objectTypeId} \
  --header 'Authorization: Bearer <token>'

{
  "results": [
    {
      "propertyName": "<string>",
      "propertyValidationRules": [
        {
          "ruleArguments": [
            "<string>"
          ],
          "ruleType": "AFTER_DATETIME_DURATION",
          "shouldApplyNormalization": true
        }
      ]
    }
  ]
}