For AI agents: the documentation index is at /llms.txt, and this page is available as Markdown at /documentation/exchange-overview.md.

Exchange overview

The True Markets exchange is a central limit order book. Its matching engine fills each incoming order against resting orders in price-time priority: the best price first, and the earliest order at that price first.

Trades settle on-chain to your True Markets wallet. You fund trading from the wallet, and every trading pair is quoted in a stablecoin.

Order types

A limit order buys or sells a quantity at a price you set or better. Use it when the price matters more than filling right away.

A market order buys or sells a quantity at the best prices on the book. Use it when filling right away matters more than the price.

Time in force

Time in force (TIF) sets how long an order stays on the book.

  • Good Till Canceled (GTC): the order rests until it fills completely or you cancel it.
  • Immediate Or Cancel (IOC): the order fills what it can against the book right away, and the exchange cancels the rest.

A market order never rests on the book, whatever its time in force.

Order checks

  • Price bands: the exchange rejects an incoming order priced too far from the current market. See Price bands.
  • Increment sizes: every price and quantity must be a multiple of the minimum increment for its price range. See Increment sizes.

The Rulebook has the full trading rules.

Protocols

You reach the exchange over REST, WebSocket or FIX. REST and WebSocket are reachable over the internet. FIX runs over a private network connection that we set up with your firm.

ProtocolUse it forAuthenticationReference
RESTorders, balances, trade history and market data over HTTPSa JWT minted from your API key, in Authorization: BearerCeFi direct REST
WebSocketstreaming order books, trades and instrument updatesan ES256 signature from your API key in the subscription message; public channels need noneCeFi direct WebSocket
FIXlow-latency order entry, market data and drop copya Logon (35=A) signed with your API key that opens the sessionCeFi direct FIX

FIX (Financial Information eXchange) is the standard protocol for institutional order flow. Drop copy is a read-only FIX session that mirrors every execution on your account, for allocation, compliance and audit.

You create your API key at app.truemarkets.co. Access and credentials explains how.

Support

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