How markets work

Every market on the STX exchange is a binary outcome contract: it either resolves yes or no. When a market resolves, every outstanding contract settles at either the market’s maxPrice (typically $100, represented as 10000 in the API) or at $0. The market’s description field is the definitive statement of what constitutes a “yes” result:

{
  "description": "Contracts for this market settle into $100 if the Boston Red Sox beats the
   New York Yankees by at least 1.5 runs and $0 if they do not.",
  "marketId": "becf9bf9-e2ff-4b50-879b-46054ad5c69a",
  "shortTitle": "NYY @ BOS -1.5"
}

Buying a contract means you believe the outcome described will happen. Selling means you believe it won’t. You are always trading against other participants on the exchange — not against STX.

Prices

All prices in the API are integer cents. A price of 4500 means $45.00. The spread between the best available bid and offer represents the current market consensus.

The maxPrice field on a market (typically 10000) is the settlement value for a winning contract. It is also the reference point for calculating sell-order liability (see Understanding Positions).

Market Status

Status	Meaning
`pre_open`	Market created but not yet accepting orders
`open`	Orders can be placed and matched
`suspended`	Temporarily halted — existing orders remain in the book
`closed`	No new orders; awaiting official result
`cancelled`	Market voided — all contracts refunded at cost
`archived`	Settled and removed from active listings

Querying Markets

Use the marketInfos query to fetch current markets. Because this endpoint requires no authentication and is heavily cached, you can call it frequently — it is designed to handle high query rates.

A minimal query for an odds display or market screener:

query {
  marketInfos(input: { filterBy: LIVE_AND_UPCOMING }) {
    marketId
    shortTitle
    title
    sport
    competition
    status
    result
    participants {
      abbreviation
      name
      role
    }
    bids(limit: 1) {
      price
      quantity
    }
    offers(limit: 1, sort: ASC) {
      price
      quantity
    }
  }
}

The top bid and offer prices are sufficient to calculate the current implied probability for either side of the market. For example, a best bid of 5701 and a best offer of 5950 implies the market is trading around 58–60 cents, or roughly a 58–60% probability of the “yes” outcome.

Filtering by Category

Markets are organised into a filter tree. Use the marketFilter input to query a specific category:

query {
  marketInfos(
    input: { marketFilter: { path: ["NFL", "Games"], group: BASIC } }
  ) {
    marketId
    shortTitle
  }
}

There are two grouping schemes:

BASIC — reflects the current app category, and changes as events progress (e.g., a market moves from “Upcoming” to “Live”).
TRADE — participant-centric; rarely changes once set.

Use marketFilterTreeV2 to retrieve the full filter tree for your current markets.

Real-Time Updates

Querying marketInfos gives you a snapshot. To receive live price and status changes without polling, subscribe to the market_info WebSocket channel, which pushes only the changed fields whenever a market is updated.