What you can do

One SDK works against every STX exchange. Not every exchange has every feature yet: OAuth apps are on US demo first, for example. A call that needs a feature the exchange does not have throws STXNotAvailableException, and capabilities() tells you up front, so the same code runs against Ontario production today and picks up new features as each exchange gets them.

Features and their calls

Feature	Id	SDK calls	Guide
Markets, events and prices		markets(), iterMarkets(), market(), events(), iterEvents(); channels ws.ticker(), ws.market(), ws.orderbook(), ws.trades(), ws.marketStats(), ws.marketUpdates()	Markets, WebSockets
Trading		placeOrder(), placeOrders(), cancelOrder(), cancelOrders(), cancelAllOrders(), order(), orders()	Trading
Your account		me(), balance(), positions(), fills(), settlements(), deposits(), withdrawals(), fees(), accountMarketStats(); channels ws.accountView(), ws.balances(), ws.orders(), ws.fills(), ws.positions(), ws.settlements()	Portfolio
Event players	event_players	eventPlayers(), statsFor()	Markets
Leaderboard and public profile	leaderboard	leaderboard(), leaderboardMe(), updateProfile()	Leaderboard
Combos	combos	ws.comboPlayer(), ws.comboMaker()	Combos
OAuth	oauth	discoverMetadata(), OAuthClient.discover()	Build an app
Members connect their STX account	oauth.member	oauth.beginAuthorization(), oauth.completeAuthorization(), oauth.memberClient(), oauth.refreshToken(), oauth.unlink(), oauth.revoke()	Sign in with STX
App tokens	oauth.app	oauth.appClient(), oauth.appToken(), oauth.clientCredentials()	Acting as your app
Sign in with STX	connect	createConnect(): start(), finish(), refresh(), disconnect(), userInfo()	Sign in with STX
Terms accepted on an STX page	terms.stx_page	STXTermsRequiredException.termsUrl, termsUrlWithReturn(), the onTermsRequired session hook	When STX has new terms
Creating markets	markets.create	createMarkets() (with dryRun), as an app holding markets.write	Creating markets
Market types	market_types	marketTypes()	Creating markets

Features without an id are on every exchange. Members still being verified (STXAccountPendingException) and IP allow-list refusals (STXIPNotAllowedException) come with OAuth wherever it is on.

Where each feature is available

Checked against the live exchanges on 2026-10-21, and Ontario demo again on 2026-10-23.

Feature	US demo (demo.stxapp.io)	Ontario demo (demo.stxapp.ca)	Ontario production (api.on.stxapp.ca)
Markets, trading, your account	yes	yes	yes
event_players	yes	yes	yes
leaderboard	yes	no	no
oauth	yes	no	no
oauth.member	yes	no	no
oauth.app	yes	no	no
connect	yes	no	no
terms.stx_page	yes	no	no
markets.create	yes	no	no
market_types	yes	no	no
Exchange version (/api_version)	3.3.196	3.3.194-5	3.3.186-6

Exchanges gain features with their releases, so ask the exchange rather than this table when your code needs to know.

Ask the exchange: capabilities()

import { STX } from "@stxapp/stx-typescript";

const stx = new STX({ environment: "ontario-demo" });
const caps = await stx.capabilities();
console.log(caps.toJSON());

On Ontario demo:

{
  "host": "demo.stxapp.ca",
  "apiVersion": "3.3.194-5",
  "checkedAt": "2026-10-23T17:37:03.512Z",
  "scopesSupported": [],
  "features": {
    "oauth": false,
    "oauth.member": false,
    "oauth.app": false,
    "connect": false,
    "terms.stx_page": false,
    "markets.create": false,
    "market_types": false,
    "event_players": true,
    "leaderboard": false,
    "combos": true
  }
}

On US demo every feature is true, and scopesSupported is the list the exchange publishes:

[
  "openid", "profile.read", "balance.read", "portfolio.read", "orders.read",
  "transfers.read", "orders.write", "market_data", "events", "markets.write"
]

• caps.features.combos is true, false, or null when it could not be checked (a check that needs credentials on a client without them, or an exchange that did not answer).
• caps.has("combos") is true only when the exchange is known to have it.
• caps.require("combos") throws STXNotAvailableException when the exchange is known not to have it.

The answer is cached on the client; capabilities({ refresh: true }) checks again. A missing feature never makes capabilities() or new STX() throw, and the calls you already make are unaffected: only a call that needs the missing feature throws.

How each feature is decided

Every check reads what the exchange publishes. Nothing is created, changed or cancelled.

Id	Available when
oauth	GET /.well-known/oauth-authorization-server returns the discovery document. A 404, or a 403 page from in front of the exchange (not JSON), means no.
oauth.member	OAuth is on, grant_types_supported lists authorization_code, and scopes_supported lists a member scope such as orders.read.
oauth.app	OAuth is on and grant_types_supported lists client_credentials.
connect	OAuth is on and scopes_supported lists openid.
terms.stx_page	Members can connect and scopes_supported does not list terms.write.
markets.create	App tokens are on and scopes_supported lists markets.write.
market_types	A signed GET /api/v1/types answers. A 404 with {"error": "not_found"} (no such route) means no.
event_players	A signed GET /api/v1/events/{event_id}/players for an event that does not exist answers 404 {"error": "event not found"}. A 404 {"error": "not_found"} means no such route.
leaderboard	A signed GET /api/v1/leaderboard?limit=1 answers. A 404 (no such route, or {"error": "Leaderboard is not enabled"}) means no.
combos	A join of the combo player topic for a user id nobody has is refused as unauthorized. unmatched topic means the exchange has no combo topics.

The OAuth discovery document and its fields are described in OAuth, and the combo topics in Combo negotiation.

When a feature is not available

STXNotAvailableException extends STXAPIException, so it is an STXException like every other SDK error. It carries:

• feature: the id from the tables above, or scope:<name> for a scope the exchange does not offer.
• host: the exchange that answered.
• message: a sentence naming both.
• statusCode and body: the answer it was decided from, when there was one.

Captured on Ontario demo on 2026-10-21:

await stx.marketTypes();
// STXNotAvailableException: Market types are not available on demo.stxapp.ca yet.
//   feature: "market_types", host: "demo.stxapp.ca", statusCode: 404, body: { error: "not_found" }

await discoverMetadata("https://demo.stxapp.ca");
// STXNotAvailableException: OAuth is not available on demo.stxapp.ca yet.
//   feature: "oauth", host: "demo.stxapp.ca", statusCode: 404

STXCombosUnavailableException is still the channel exception it was, and instanceof STXNotAvailableException is true for it too, so either catch works:

import { STXNotAvailableException } from "@stxapp/stx-typescript";

try {
  const player = await ws.comboPlayer();
  // ...
} catch (err) {
  if (err instanceof STXNotAvailableException) {
    console.log(`${err.feature} is not on ${err.host} yet; hiding combos`);
  } else {
    throw err;
  }
}

Which calls throw it, by feature:

Id	Throws from
combos	ws.comboPlayer(), ws.comboMaker()
oauth	discoverMetadata(), OAuthClient.discover(), and any token, refresh, revoke or introspect call on an exchange without OAuth
connect	createConnect() calls, when the exchange has no OpenID configuration or userinfo endpoint
market_types	marketTypes()
event_players	eventPlayers(), statsFor()
leaderboard	leaderboard(), leaderboardMe(), updateProfile()
markets.create	createMarkets()
scope:<name>	clientCredentials(), appClient() calls and completeAuthorization(), when the exchange answers invalid_scope for a scope its discovery document does not list (the client must come from OAuthClient.discover() or fromMetadata() to know the list)