curl --request POST \
  --url https://synthesis.trade/api/v1/markets/orderbooks \
  --header 'Content-Type: application/json' \
  --data '
{
  "markets": [
    "21742633143463906290569050155826241533067272736897614950488156847949938836455",
    "KXBTC-25-T100000"
  ]
}
'

{
  "success": true,
  "response": [
    {
      "venue": "polymarket",
      "orderbook": {
        "condition_id": "0xbd71b43bb47eb60dbcb41fa25df2a0ed4da612873d6e0447a2c730bd4cc25910",
        "token_id": "21742633143463906290569050155826241533067272736897614950488156847949938836455",
        "bids": {
          "0.61": "1000",
          "0.60": "800"
        },
        "asks": {
          "0.62": "900",
          "0.63": "600"
        },
        "best_bid": "0.61",
        "best_ask": "0.62",
        "hash": "abc123",
        "created_at": "2026-01-01T00:00:00"
      }
    },
    {
      "venue": "kalshi",
      "orderbook": {
        "market_id": "KXBTC-25-T100000",
        "yes": {
          "bids": {
            "58": "25"
          },
          "asks": {
            "60": "15"
          },
          "best_bid": "58",
          "best_ask": "60"
        },
        "no": {
          "bids": {
            "40": "15"
          },
          "asks": {
            "42": "20"
          },
          "best_bid": "40",
          "best_ask": "42"
        },
        "sequence": 12345,
        "created_at": "2026-01-01T00:00:00"
      }
    }
  ]
}