Hello,
Thank you for writing to us. Please find my response to your queries below.
When getting Ad via the API (either AdWords or Ads v2), what field(s) differentiate "normal Ad from manual input" from "auto-applied Ad suggestion's Ad": You could use the ad_group_ad resource to retrieve the details for the ads created manually or Google Ads in your account via API. The field "ad_group_ad.ad.added_by_google_ads" will indicate whether the ad is added by Google Ads as suggestions for new ads. To retrieve the ad suggestions, you could also use the recommendation resource. Please refer to this guide for more details on recommendation types and getting these via API.
Through research the Ad in AdWords have field "automated" and Ads v2 have "added_by_goolge_ads", is this what I'm looking for? Both the field only have vague description, and only of type Boolean, & feel like it can encompass multiple scenario, is it guarantee that it only for "auto-applied Ad suggestion": Yes, these fields indicates that the ads are automatically added as ad suggestions and are not added manually or via API.
Regards,
Nikisha Patel, Google Ads API Team