Market data for Kalshi and Polymarket.

List markets, fetch price history, inspect supported trades and current order books, and resolve weather contracts against the public data that settles them. Shared schemas cover the fields both venues provide.

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market_data.py

 from mostlyright import markets

prices = markets.kalshi.ohlcv(
    "KXHIGHNY-25MAY26-T79",
    resolution="1h",
    from_ts="2025-05-25T00:00Z",
    to_ts="2025-05-26T00:00Z",
)

prices[["bucket_start_utc", "probability", "source"]]

Contracts, prices, and settlement data.

Query the market itself, then connect weather contracts to the public record used to settle them.

Discover markets

List contracts with status, close time, bid, ask, last price, volume, and venue identity.

Fetch price history

Query Kalshi and Polymarket with one OHLCV vocabulary and a documented UTC time axis.

Resolve settlement

Map weather contracts to the station, source, date, unit, and rule each venue names.

One schema where venues overlap.

Shared fields use the same names and units. Venue-specific values remain visible, and unsupported calls raise a typed error.

markets.ohlcv() normalized row

market_id KXHIGHNY…T79

bucket_start_utc 2025-05-25T19:00Z

probability 0.567

source kalshi

Identity: Every row retains its ticker, market, event, or outcome-token identifier.
Price: Probability is normalized to 0–1. The venue-native price remains available.
Volume: Contracts, USD, or the venue-native unit stays explicit beside the value.
Time and source: UTC bucket time and the originating venue stay attached to every returned row.

Market data without hiding venue differences.

Use the same verbs for shared data. Keep native identifiers, price values, volume units, and capability limits explicit when Kalshi and Polymarket differ.

compare_venues.py

 # Same verb. Venue-specific identity.
kalshi = markets.kalshi.ohlcv(
    ticker, resolution="1m", from_ts=start, to_ts=end
)

polymarket = markets.polymarket.ohlcv(
    token_id, resolution="1m", from_ts=start, to_ts=end
)

kalshi.schema_id == polymarket.schema_id
# True

01
MarketsStatus, close time, bid, ask, and last
02
Price historyShared OHLCV rows and UTC buckets
03
TradesVenue-supported fills with price and size
04
Order booksCurrent price levels and available size

From market identity to usable rows.

Choose the venue and identifier. Request the data you need. Keep its units, timestamps, and source attached.

01

Choose the venue and market

Start with a Kalshi ticker, Polymarket event, or outcome token.
02

Request the data

List markets, fetch price history, or read the supported trades and current book.
03

Use the returned rows

Receive stable fields with price units, UTC timestamps, identifiers, and source attached.

Query Kalshi and Polymarket through one API.