Analytics API paging object pageSize vs pageCount confusion

Getting inconsistent results when querying /api/v2/analytics/conversations/details/query. The response says pageSize is 1000 and pageNumber is 1, but pageCount is 5 even though I only get 200 records back.

{
 "pageSize": 1000,
 "pageNumber": 1,
 "pageCount": 5,
 "items": [...200 items...]
}

Is the SDK ignoring the pageSize limit or am I misinterpreting the paging logic for this endpoint?