+1 to @danielpomeranz’s point. The product team is working through how to best integrate this functionality into the platform. For now, the “mode hack” as a lot of folks refer to it is the best way to do things like lookup functions
Just confirming, but you will have to set up the runAggregation API call to use a limit of 1 and be filtered and sorted accordingly.
I also would not be surprised if there were some bugs with this as it is new functionality. If you can isolate this example and send it to Tulip support, I would not be surprised if an edge case was missed such as the ability to have the function return Timestamp values.