GET /v1/book/deltas

Incremental updates between two timestamps.

Request

GET /v1/book/deltas?source=polymarket&market=btc-updown-15m-1792681200&outcome=up&start=2026-10-22T15:10:00Z&end=2026-10-22T15:11:00Z
Authorization: Bearer YOUR_API_KEY

Response

{
  "data": [
    {
      "ts_exchange": "2026-10-22T14:30:00.240Z",
      "side": "bid",
      "price": 0.52,
      "size": 19100,
      "seq": 482911
    },
    {
      "ts_exchange": "2026-10-22T14:30:00.241Z",
      "side": "ask",
      "price": 0.55,
      "size": 0,
      "seq": 482912
    }
  ],
  "next_cursor": null
}

size: 0 means the level was removed. Apply deltas in seq order on top of a snapshot.