curl --request GET \
  --url https://api.rekko.ai/v1/arbitrage

{
  "count": 1,
  "opportunities": [
    {
      "cheaper_on": "kalshi",
      "event": "Fed rate cut March 2026",
      "kalshi": {
        "market_id": "KXFED-26MAR19",
        "url": "https://kalshi.com/markets/kxfed/kxfed-26mar19",
        "yes_price": 0.62
      },
      "match_confidence": 0.92,
      "polymarket": {
        "market_id": "0x1234abcd",
        "url": "https://polymarket.com/event/fed-rate-cut-march-2026",
        "yes_price": 0.68
      },
      "scanned_at": "2026-03-21T14:30:00Z",
      "score": 78,
      "spread": 0.06,
      "spread_pct": 6
    }
  ],
  "scanned_at": "2026-03-21T14:30:00Z"
}