Probability surface

The surface

One call per horizon, four families in one payload: per-venue legs, gated consensus, the options-vs-PM wedge, and touch markets. metal is xau or xag; optional ?horizon=YYYY-MM-DD selects a bucket from the expiries index. Unknown horizons return 404 unknown_horizon with the live list.

Sample response

{
  "result": "success",
  "metal": "xau",
  "timezone": "UTC",
  "as_of": "2026-07-06T14:30:00Z",
  "served_at": "2026-07-06T14:31:12Z",
  "snapshot_age_seconds": 72,
  "max_staleness_seconds": 180,
  "methodology": "last_trade@1",
  "horizon": {
    "target": "2026-07-10",
    "alignment": "tight",
    "max_span_hours": 24,
    "venues_live": ["options", "kalshi"],
    "venues_missing": [
      {"venue": "polymarket", "reason": "no_market_at_horizon"}]
  },
  "reference_spot": {
    "usd": "4123.50", "source": "pyth_xauusd",
    "tradeable_book": false
  },
  "legs": [
    {"venue": "options", "underlying": "GLD", "expiry": "2026-07-10",
     "trading_day": "2026-07-06", "state": "live", "market_open": true,
     "semantics": "terminal_above", "settlement_ref": "gld_nav",
     "measure": "risk_neutral",
     "points": [
       {"threshold_usd": "4100", "prob_above": "0.61",
        "last_trade_age_seconds": 41},
       {"threshold_usd": "4200", "prob_above": "0.34",
        "last_trade_age_seconds": 187}]},
    {"venue": "kalshi", "series": "KXGOLDW",
     "close_time": "2026-07-10T20:00:00Z",
     "trading_day": "2026-07-06", "state": "live",
     "semantics": "terminal_above", "settlement_ref": "kalshi_index",
     "measure": "real_world", "quote_scale": "probability_0_1",
     "points": [
       {"threshold_usd": "4100", "prob_above": "0.63",
        "yes_bid": "0.61", "yes_ask": "0.65",
        "bid_size": "1250", "ask_size": "900"}]}
  ],
  "consensus": [
    {"threshold_usd": "4100", "prob_above": "0.62", "venues": 2,
     "max_divergence": "0.02",
     "measures": ["risk_neutral", "real_world"],
     "settlement_refs": ["gld_nav", "kalshi_index"]}
  ],
  "wedge": {
    "available": true,
    "options_market_open": true,
    "points": [{"threshold_usd": "4100", "options_minus_pm": "-0.02"}]
  },
  "touch": []
}

Honesty fields

served_at and snapshot_age_seconds make the stacked 60-second caches measurable per request, plus a standard Age header. reference_spot is labeled tradeable_book: false: there is no real spot bid/ask, from us or anyone. Prediction-market quotes carry quote_scale so a 61-cent contract bid is never mistaken for a gold-price bid. Legs that settle mid-session flip to state: "settled" and are served from a grace snapshot, never silently vanished. Silver has no Polymarket leg, so XAG never has a wedge; the response says available: false, reason: "no_pm_leg".

Horizon index

The front door for "what dates can I ask about?". Every servable target-date bucket, its venues, and its alignment grade. default: true marks the bucket the surface serves with no horizon parameter.

Sample response

{
  "result": "success",
  "metal": "xau",
  "timezone": "UTC",
  "as_of": "2026-07-06T14:30:00Z",
  "horizons": [
    {"target": "2026-07-07", "alignment": "tight",
     "venues": ["options", "kalshi"], "default": false},
    {"target": "2026-07-10", "alignment": "tight",
     "venues": ["options", "kalshi"], "default": true},
    {"target": "2026-12-31", "alignment": "loose", "max_span_days": 13,
     "venues": ["options", "polymarket"],
     "note": "options expire 2026-12-18; polymarket settles 2026-12-31 on cme_gc"}
  ]
}

Arbitrage signals

Cross-venue executable-edge detection swept across every live horizon. Populated rarely; the empty array below is the honest, normal case. Our own published research found zero executable gold arb across a full trading day, and the endpoint reflects that reality instead of manufacturing signals.

Sample response

{
  "result": "success",
  "metal": "xau",
  "signals": []
}