# Acme

> Acme is an invoicing API for small businesses. This file lists the pages an AI assistant needs to answer questions about Acme and to write code against its API.

The API is REST over HTTPS with JSON bodies. Every request needs an API key in the `Authorization` header. Amounts are integers in the smallest currency unit, so 1999 means 19.99.

## Docs

- [Quickstart](https://acme.dev/docs/quickstart.md): Create an API key and send your first invoice in five minutes
- [Authentication](https://acme.dev/docs/authentication.md): API keys, test and live mode, and key rotation
- [Invoices](https://acme.dev/docs/invoices.md): Create, send, void and list invoices
- [Webhooks](https://acme.dev/docs/webhooks.md): Event types, payloads and how to verify signatures
- [Errors](https://acme.dev/docs/errors.md): Error codes and which ones are safe to retry

## API reference

- [OpenAPI specification](https://acme.dev/openapi.json): Every endpoint, parameter and response schema
- [Node SDK](https://github.com/acme/acme-node): Official TypeScript client with examples

## Product

- [Pricing](https://acme.dev/pricing.md): Plans, limits and what counts as an invoice
- [Security](https://acme.dev/security.md): Data storage, encryption and compliance

## Optional

- [Changelog](https://acme.dev/changelog.md): API changes by version
- [Blog](https://acme.dev/blog.md): Guides and product news