Market data - Mithril

Market data is one normalized plane across Kalshi and Polymarket: prices are probabilities in (0, 1), books are unified, and one mkt_ ID maps the same event on both venues.

Search markets

Discovery is search-driven. Pass a query (and optional limit):

curl "https://api.trymithril.com/v1/markets?query=world%20cup&limit=5" \
  -H "Authorization: Bearer $MITHRIL_API_KEY"

mkts = s.get(f"{BASE}/v1/markets", params={"query": "world cup", "limit": 5}).json()["data"]
market = mkts[0]
print(market["id"], market.get("question"))

Each result (MarketView) in the data array:

{
  "id": "mkt_...",
  "exchange": "polymarket",
  "exchange_market_id": "0x...",
  "question": "Will Argentina win the World Cup?",
  "outcomes": [
    { "token_id": "7194...", "label": "Yes", "price": "0.42" },
    { "token_id": "1088...", "label": "No",  "price": "0.58" }
  ],
  "status": "open",
  "close_time": "2026-12-18T00:00:00Z",
  "volume_24h": "48210.00",
  "resolved": false
}

Read the orderbook

The orderbook gives you a tradable token_id (which outcome you’re buying) plus live depth:

curl https://api.trymithril.com/v1/markets/mkt_.../orderbook \
  -H "Authorization: Bearer $MITHRIL_API_KEY"

ob = s.get(f"{BASE}/v1/markets/{market['id']}/orderbook").json()
token_id = ob["token_id"]
best_bid = float(ob["bids"][0]["price"]) if ob["bids"] else 0.0
best_ask = float(ob["asks"][0]["price"]) if ob["asks"] else 1.0
print(f"bid {best_bid:.3f} / ask {best_ask:.3f}  spread {best_ask - best_bid:.3f}")

The orderbook (OrderbookView) — bids and asks are {price, size} levels:

{
  "market_id": "mkt_...",
  "token_id": "7194...",
  "bids": [ { "price": "0.41", "size": "1200" }, { "price": "0.40", "size": "3400" } ],
  "asks": [ { "price": "0.43", "size": "900" },  { "price": "0.44", "size": "2600" } ]
}

Prices and history

Endpoint	Returns
`GET /v1/markets/{id}`	Full market detail
`GET /v1/markets/{id}/orderbook`	Live L2 book + `token_id`
`GET /v1/markets/{id}/prices`	Recent price series
`POST /v1/markets/match`	Map an event to its equivalent `mkt_` across venues

curl "https://api.trymithril.com/v1/markets/mkt_.../prices?limit=50" \
  -H "Authorization: Bearer $MITHRIL_API_KEY"

GET /v1/markets/{id}/prices returns a PricesView:

{
  "market_id": "mkt_...",
  "token_id": "7194...",
  "interval": "1h",
  "points": [ { "timestamp": "2026-07-16T13:00:00Z", "price": "0.41" } ]
}

POST /v1/markets/match takes { "exchange": "kalshi", "exchange_market_id": "..." } and returns the unified mkt_ market, creating the mapping on first sight.

Market data today is served over REST. If you need the freshest book, poll the orderbook endpoint; the smart execution engine reads live depth for you when working an order.

Next: Guardrails

Set the limits every order is checked against before you place one.

​Search markets

​Read the orderbook

​Prices and history

Next: Guardrails

Search markets

Read the orderbook

Prices and history