---
title: API reference
description: REST API documentation for the Seamless OS platform: billing, subscriptions, payments, and telecom services
---

## Seamless OS API reference

With the Seamless OS REST API you can sell telecom services, manage customers, and bill
them. The pages that follow cover the integration styles, the API conventions, and the
customer journey from an order to an invoice.

## Getting started

- [Get started](/api-reference/get-started.md) — Place your first order with the API.
- [Choose your integration](/api-reference/choose-your-integration.md) — Pick the integration style that fits your business model.

## API fundamentals

- [Conventions](/api-reference/conventions.md) — The design principles and the naming patterns of the API.
- [Authentication](/api-reference/authentication.md) — API keys, user tokens, and how to keep them safe.
- [Errors](/api-reference/errors.md) — The structure of an error response, and what each status code means.
- [Rate limiting](/api-reference/rate-limiting.md) — The request limits, and how to retry when you reach one.


## Reference pages

- [Auth](/api-reference/auth.md) — Authenticate users and obtain access tokens.
- [Customers](/api-reference/customers.md) — Manage customers.
- [Inventory](/api-reference/inventory.md) — Manage phone number inventory, SIM cards, and reservations.
- [Invoices](/api-reference/invoices.md) — Manage invoices and invoice items.
- [Licenses](/api-reference/licenses.md) — Manage licenses.
- [Orders](/api-reference/orders.md) — Manage orders and line items.
- [Payment Intents](/api-reference/payment-intents.md) — Inspect payment intents, the money collected over card rails for orders and renewals.
- [Payment Links](/api-reference/payment-links.md) — Create and manage payment links for orders and invoices.
- [Payment Profile Sessions](/api-reference/payment-profile-sessions.md) — Create sessions for setting up payment profiles.
- [Payment Profiles](/api-reference/payment-profiles.md) — Manage customer payment profiles and methods.
- [Payment Sessions](/api-reference/payment-sessions.md) — Create and manage payment sessions for orders.
- [Porting](/api-reference/porting.md) — Manage number porting for subscriptions.
- [Product Catalogs](/api-reference/product-catalogs.md) — Browse product catalogs.
- [Product Discounts](/api-reference/product-discounts.md) — Discounts and promotions.
- [Product Offerings](/api-reference/product-offerings.md) — Browse product offerings.
- [Reports](/api-reference/reports.md) — Retrieve generated reports and download their files.
- [Subscribers](/api-reference/subscribers.md) — Manage subscribers.
- [Subscription Addons](/api-reference/subscription-addons.md) — Manage subscription addons.
- [Subscription Usage](/api-reference/subscription-usage.md) — Get subscription usage.
- [Subscriptions](/api-reference/subscriptions.md) — Manage subscriptions and subscription.
- [Tools](/api-reference/tools.md) — Tools for address validation, number porting, device info, and network coverage.
- [Users](/api-reference/users.md) — Manage users.
- [Workflows](/api-reference/workflows.md) — Dynamic processing of customer journeys and events.
- [Webhook events](/api-reference/webhook-events.md) — Every event the API sends, grouped by the resource that emits it.
- [Schemas](/api-reference/models.md) — Every request, response and webhook payload schema in the API.