@gpmpay/sdk/docs/en/README.md

Official Node.js SDK for GPM Pay — VietQR codes, transaction webhooks, and payment reconciliation.

# @gpmpay/sdk documentation (English)

[Tiếng Việt](../vi/README.md) · [Package README](../../README.en.md)

1. **[Getting started](./01-getting-started.md)** — create a token, install, first payment, end-to-end test without real money
2. **[Payments & reconciliation](./02-payments.md)** — the payment model, choosing a code, matching pitfalls, money types, VietQR
3. **[Webhooks end to end](./03-webhooks.md)** — registration, signature verification, Express/Next/other frameworks, retries, debugging
4. **[Errors & testing](./04-errors-and-testing.md)** — error tree, retry policy, sandbox, unit tests
5. **[API reference](./05-api-reference.md)** — every option, method, and type

## What to read first

| You want to | Read |
|---|---|
| Take a payment as fast as possible | 1 → 3 |
| Understand why a payment didn't match | 2 ("Choosing the code") |
| Fix a webhook that always fails verification | 3 ("Troubleshooting") |
| Write tests for the integration | 4 |
| Look up a method signature | 5 |
| Have an AI agent do the integration | [`AGENTS.md`](../../AGENTS.md) |

## Runnable examples

See [`examples/`](../../examples/):

- `self-reconcile/` — Express: checkout builds the QR, webhook route matches it. **Start here.**
- `next-app-router/` — Next.js App Router, server action + route handler