# API

* Contract API: All trades are executed within contracts on Sonic. To set an order, you call the contract entry point.
* The HTTP API allows you to retrieve information about past and current prices, orders, and trades.
* The WebSocket API is used to receive events about recent changes.

Interaction is available on mainnet with:

* two market contracts [SUSDC](https://sonicscan.org/address/0xc7723fe3df538f76a063eb5e62867960d236accf) and [ETHUSDC](https://sonicscan.org/address/0x75aba7081182a2b1f3b0ead47c074e800805941e)​
* HTTP base endpoint <https://api.xpressprotocol.com>[​](https://api.xpressprotocol.com)
* WebSocket endpoint `wss://sockets.xpressprotocol.com`


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.xpressprotocol.com/for-developers/api.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.