# v2 (latest)

The remaining sections of the documentation will demonstrate specific examples of the DEX usage:

* [perform a swap operation](https://docs.ston.fi/developer-section/dex/sdk/v2/swap)
* [provide liquidity](https://docs.ston.fi/developer-section/dex/sdk/v2/provide-liquidity)
* [refund liquidity](https://docs.ston.fi/developer-section/dex/sdk/v2/refund-liquidity)
* [burn liquidity tokens](https://docs.ston.fi/developer-section/dex/sdk/v2/burn-lp-tokens)
* [withdraw fee from vault](https://docs.ston.fi/developer-section/dex/sdk/v2/vault-operations)

## Referral Fees

DEX v2 stores each swap's referral portion in a dedicated `Vault` contract (one per `referrer × token` pair). The fee percentage can be set between **0.01 % and 1 %** and must be withdrawn later by the referrer.

Inspect vault balances and history using the Stats & Vaults REST API:

* `GET /v1/wallets/{addr_str}/fee_vaults` – lists all known vaults per referrer
* `GET /v1/stats/fee_accruals` – shows all operations leading to fee accrual for the referrer, filterable by period
* `GET /v1/stats/fee_withdrawals` – lists withdrawals from the referrer's vaults by period
* `GET /v1/stats/fees` – returns aggregated referral fee information, for example total accrued USD value

See the Omniston [referral fees guide](https://docs.ston.fi/omniston/referral-fees#referral-fees-with-dex-v2) (note: although the guide is Omniston-oriented, the referenced paragraph explains DEX V2 referral fees in detail). Full API documentation is available in the [Swagger UI](https://api.ston.fi/swagger-ui/#/).