MidChains offers two different APIs that have account and order management as well as public market data: Websocket WebSocket API and FIX API. You can choose which is most appropriate based on your needs.
The Websocket WebSocket API includes standard endpoints that are used by a wide variety of web services.
The FIX API uses FIX (Financial Information eXchange), a standard protocol which that can be used to enter orders, submit cancel requests, and receive fills. Users of the FIX API will typically have existing software using FIX for order management. Users who are not familiar with FIX should first consider using the Websocket WebSocket API.