Tactic performance data is available via API but not directly, so there are few calls and lookups you need to do in order to get this information.

In order to get tactic delivery information from Agency Analytics, you will need to make multiple calls:

From the v1/stats endpoint, you should be able to filter that for whatever line item and/or campaign ID you are looking to filter for. Then the result from v1/stats should give you a delivery_source_id which you should be able to use with the v1/delivery_sources/{id} endpoint to get external_id and the external_id would be the tactic ID.