The Analytics API includes the
/2/searches/count endpoint which provides an aggregated total of searches. This data can be filtered / segmented using tags which is very useful.
It would be even better if the non-aggregated query count was also available via this API so we can understand complete usage for our tags and apportion requests we are billed for to specific users or groups.
The Usage API gives us non-aggregated counts but without the ability to filter by tags.