Unfortunately, you cannot delete an
AdGroupFeed via the API once its associated
AdGroup has been deleted. To filter out
AdGroupFeeds for your deleted
AdGroups, you could periodically poll
AdGroupService (or use
AD_GROUP_PERFORMANCE_REPORT) and collect the IDs of
REMOVED ad groups, then exclude those IDs using a predicate on
AdGroupId when making your
AdGroupFeedService.get requests.