> ## Documentation Index
> Fetch the complete documentation index at: https://docs.paygood.com/llms.txt
> Use this file to discover all available pages before exploring further.

# PayGood Payments API: Developer Overview and Guide

> PayGood is a REST API for accepting payments, managing customers, and onboarding merchants. Discover what you can build and how to get started.

PayGood is a REST API that gives you everything you need to accept payments, manage customers, and onboard merchants into your platform. Whether you're building a marketplace, a SaaS billing system, or a point-of-sale integration, PayGood provides the primitives to move money reliably and at scale.

## What you can build

<CardGroup cols={2}>
  <Card title="Payments" icon="credit-card" href="/guides/first-payment">
    Create, capture, and refund payments. Support one-time charges and authorize-and-capture flows for your customers.
  </Card>

  <Card title="Customers" icon="users" href="/guides/manage-customers">
    Store and manage customer profiles. Attach payment instruments and retrieve transaction history for any customer.
  </Card>

  <Card title="Payment Instruments" icon="wallet" href="/guides/payment-instruments">
    Tokenize cards and bank accounts. Securely store payment methods and reuse them for future charges without re-entering details.
  </Card>

  <Card title="Invoices" icon="file-invoice" href="/guides/invoices">
    Create draft invoices, revise line items, mark as paid, or void. Track every change with append-only revision history.
  </Card>
</CardGroup>

## Supported currencies

PayGood currently supports the following currencies for payment processing:

* **USD** — United States Dollar
* **CAD** — Canadian Dollar

Specify the currency using its three-letter ISO 4217 code when creating a payment. Additional currencies are planned — check the changelog for updates.

## Idempotent requests

All write operations (such as creating a payment or a customer) accept an `idempotencyKey` field in the request body. Supplying a unique key lets you safely retry a request if you experience a network timeout or other transient error — PayGood will return the result of the original operation rather than creating a duplicate. Use a UUID or another sufficiently unique string as your idempotency key.