Analytics API 413 on 90-day query split attempt

Hitting a 413 Entity Too Large when POSTing to /api/v2/analytics/conversations/details/query. The payload is just a 90-day date range with a standard viewId. I’m trying to chunk this by week using the SDK’s analyticsApi.postAnalyticsConversationsDetailsQuery, but the request body size limit seems to be tripping on the initial query definition itself, not just the response.

const body = {
 viewId: 'conversations',
 dateFrom: '2023-10-01T00:00:00Z',
 dateTo: '2023-12-31T23:59:59Z',
 size: 1000,
 select: ['conversationId', 'wrapUpCode'],
 groupBy: []
};
try {
 const res = await platformClient.analytics.postAnalyticsConversationsDetailsQuery(body);
} catch (e) {
 console.error(e.status); // 413
}

Reducing the range to 30 days works fine. The docs mention pagination for the response, but nothing about request body size limits for the query object. Is there a specific header or query param to enable chunking on the input side, or do I have to manually slice the dateFrom/dateTo in a loop? The SDK doesn’t seem to expose a batch method for this endpoint.