Grain API Overview

The Payments API enables merchants to accept stablecoin payments using an OTW (one-time wallet) per checkout.

The typical flow:

1

Create merchant

Create a merchant and obtain API credentials.

2

Create payment session

Create a payment session for the order amount.

3

User connects wallet and selects asset

Have the user connect a wallet and select a stablecoin + network.

4

User funds the one-time wallet

User funds the session's one-time wallet (OTW).

5

Capture funds

The merchant captures funds to complete the payment.

This documentation is organized for external integrators. Use the Quickstart to go end‑to‑end, then reference individual endpoints as needed.