# Seamless API

> A read-only GraphQL API for reading a business's own product library and sales data from Seamless POS.

- Version: 1.0.0, sent on every response as the `X-API-Version` header.
- Endpoint: `POST https://api.seamlesspos.com/graphql` with a JSON body of `{ "query": "...", "variables": { } }`.
- Authentication: `Authorization: Bearer <API key>`. Keys start with `k_live_` and are created in the Seamless backoffice.
- Read-only: there are no mutations.
- Money is an integer in the minor unit (pence) and includes tax.
- Lists that page (`products`, `orders`, `refunds`) return `nodes` and `nextCursor`; pass `nextCursor` as `after` until it is null.

## Getting started

- [Seamless API](https://dev.seamlesspos.com/introduction.md): What the Seamless API is, its endpoint and what it can read.
- [Quickstart](https://dev.seamlesspos.com/quickstart.md): Create an API key and make a first request with curl, Node.js or Python.
- [API keys and permissions](https://dev.seamlesspos.com/authentication.md): How API keys work, the four permissions, and which sites a key can read.
- [Conventions](https://dev.seamlesspos.com/conventions.md): Money in minor units, date and time formats, business dates, nulls and ids.
- [Pagination](https://dev.seamlesspos.com/pagination.md): Reading every page of products, orders and refunds with cursors.

## Guides

- [Product library](https://dev.seamlesspos.com/guides/products.md): Categories, products, prices, cost prices and modifier groups, with full request and response examples.
- [Orders and refunds](https://dev.seamlesspos.com/guides/sales.md): Orders, order lines, voids, payments, refunds and staff, with full request and response examples.
- [Daily summary](https://dev.seamlesspos.com/guides/daily-summary.md): Sales totals per business date that match Seamless reports.
- [Complete examples](https://dev.seamlesspos.com/guides/recipes.md): Two complete scripts with paging, retries and error handling. One totals a day's sales in Node.js and the other exports the product library in Python.

## Errors, limits and versioning

- [Errors](https://dev.seamlesspos.com/errors.md): Error codes, their HTTP statuses and which are worth retrying.
- [Limits](https://dev.seamlesspos.com/limits.md): Request rate, page size and date range limits.
- [Versioning](https://dev.seamlesspos.com/versioning.md): The current API version, what counts as a breaking change, and how changes are announced.

## Reference

- [GraphQL schema](https://dev.seamlesspos.com/schema.graphql): Every type, field and argument, with descriptions.
- [Everything in one file](https://dev.seamlesspos.com/llms-full.txt): All of the pages above followed by the schema.