I am looking for a way to programmatically retrieve a list of domains that I own through Google Domains (domains.google.com). I have found APIs available for Google Cloud Domains and Google Domains RDAP but these do not appear to be hooked into my Google Domains account, as when I make the API calls nothing is returned.
Has anyone found a way to do this? I am specifically going to be using PHP but if someone can just point me to the correct API (and possibly documentation) to use?