Agent utilization metrics by 30-minute intervals via Analytics API

Trying to pull granular agent utilization data using the /api/v2/analytics/agents/summary endpoint. I need tHandle, tAcw, and tHold broken down into 30-minute buckets.

Current query:

{
 "dateFrom": "2024-05-01T00:00:00.000Z",
 "dateTo": "2024-05-01T23:59:59.999Z",
 "groupBy": ["time"],
 "interval": "PT30M",
 "metrics": ["tHandle", "tAcw", "tHold"],
 "entity": {"id": "agent-id-here"}
}

The response comes back with interval set to PT1H regardless of what I pass in the request body. The API ignores the custom interval for agent summary queries. Is there a different endpoint or a specific flag I’m missing to force 30-minute granularity?