@jillblaz that’s what I would expect, zeros. However, we are actually receiving values > 0 for metrics such as “promoted_tweet_app_install_attempts” inside campaigns with objectives such as TWEET_ENGAGEMENT.
In other words, I expect that all available metrics be returned in my API response regardless of the objective type. However, for a campaign with an objective CUSTOM I would not expect to see values > 0 for metrics such as “promoted_tweet_app_install_attempts”.