En el ejemplo, la edad del cliente pasó de no tener (null) a 32 años.

{
  "trigger": "update",
  "resource_type": "Client",
  "created_at": "24/01/2020 14:59 UTC",
  "user": "[email protected]",
  "request_uuid": "d2656f36-1ce3-4788-9533-c8c84e17f591",
  "resource": {
    "id": 1,
    "first_name": "Usuario",
    "last_name": "AgendaPro",
    "email": "[email protected]",
    "identification_number": "11.111.111-1",
    "phone": "+56998877665",
    "second_phone": "",
    "age": 32,
    "birth_day": null,
    "birth_month": null,
    "birth_year": null,
    "record_number": "",
    "address": "",
    "district": "",
    "city": "",
    "custom_attributes": []
  },
  "changes": {
		"age": [
      null,32
		]
  }
}