# anybill Vendor API (POS Integration)

> anybill is a digital receipt platform for retail merchants. This index covers
> everything a point-of-sale system needs to integrate the anybill Vendor API:
> authentication, environments, the receipt endpoints and data model, store and
> loyalty endpoints, the customer display requirements, the integration review
> checklist, the C# POS SDK, the webhooks that forward receipts to merchant
> systems, and the OpenAPI specification. It follows the llmstxt.org standard and
> is intended for AI coding agents and chat assistants working on a POS
> integration. The site-wide index, including the Frontend SDKs and the Partner
> Platform API, is at https://developer.anybill.de/llms.txt.

## Architecture and Data Flow

- [Architecture and Data Flow](https://developer.anybill.de/architecture_and_data_flow/index.md): High-level overview of the anybill platform architecture, the participating systems, and how receipt data flows between merchants, customers, and third parties.

## Vendor API

- [Overview](https://developer.anybill.de/vendor_api/index.md): Getting-started checklist for integrating the Vendor API into a point-of-sale system, plus retry policy, Postman collection and license.
- [AI-Assisted Integration](https://developer.anybill.de/vendor_api/ai_assisted_integration.md): How to integrate the Vendor API into a POS system with AI coding agents or chat assistants, using this documentation, a Vendor API llms.txt and a ready-to-use AGENTS.md.
- [Environments](https://developer.anybill.de/vendor_api/environments.md): Available environments of the Vendor API and their base URLs.
- [Authentication](https://developer.anybill.de/vendor_api/authentication.md): OAuth 2.0 service-account authentication flow, scopes, access and refresh tokens for the Vendor API.
- [Bill Endpoints](https://developer.anybill.de/vendor_api/bill_endpoints.md): Routes for sending, cancelling and pre-registering receipts, user identification, and the required request fields.
- [Bill Data Model](https://developer.anybill.de/vendor_api/bill_data_model.md): Structure of the BillDTO: head, data, security and misc, plus the value reference for lines, payment types, quantity measures and currencies.
- [Fiscalization](https://developer.anybill.de/vendor_api/fiscalization.md): How to send fiscalization data in bill.security: the required and failure flags, the type discriminator, the mandatory fields per fiscalization type (TSE, RKSV, BOI-TVA, TicketBAI, Sweden, Portugal, generic) and the deprecated field names.
- [Bill Examples](https://developer.anybill.de/vendor_api/bill_examples.md): Worked payload examples for discounts on line items and whole receipts, returning a line item, and custom sections.
- [Print Buffer Format Guide](https://developer.anybill.de/vendor_api/print_buffer.md): Control-sequence format for transmitting a pre-rendered receipt layout as a print buffer.
- [Store Endpoints](https://developer.anybill.de/vendor_api/store_endpoints.md): Creating, searching and deleting stores, and the required fields of each store request.
- [Loyalty Endpoints](https://developer.anybill.de/vendor_api/loyalty_endpoints.md): Starting and cancelling loyalty transactions, linking them to receipts, and the required request fields.
- [Customer and Cashier Display](https://developer.anybill.de/vendor_api/customer_display.md): Rendering the QR code on the checkout customer display.
- [Integration Review](https://developer.anybill.de/vendor_api/integration_review.md): How the anybill POS Integration Team reviews a POS integration before go-live, what to prepare, and the questions the review goes through.

## Vendor API SDK

- [Overview](https://developer.anybill.de/vendor_api_sdk/overview.md): Summary of the C# Vendor API SDK, features and change log.
- [Configuration](https://developer.anybill.de/vendor_api_sdk/configuration.md): How to add anybill's private NuGet feed (JFrog Artifactory) as a package source in the dotnet CLI, nuget.exe, Visual Studio or a project NuGet.config.
- [C# Integration](https://developer.anybill.de/vendor_api_sdk/csharp_integration.md): End-to-end integration example for the C# SDK.

## Webhooks

- [Overview](https://developer.anybill.de/webhooks/overview.md): Authentication, headers, and common use cases for anybill webhooks.
- [Receipt Notification](https://developer.anybill.de/webhooks/receipt_notification.md): Payload and delivery semantics for the receipt-created webhook.
- [Loyalty](https://developer.anybill.de/webhooks/loyalty.md): Loyalty event webhook payload and behaviour.

## Security and Compliance

- [Security and Compliance](https://developer.anybill.de/security_and_compliance/index.md): Data-centre location, encryption, access control, availability guarantees, and the legal requirements for issuing a digital receipt.

## Downloads

- [AGENTS.md download (Vendor API)](https://developer.anybill.de/downloads/anybill-vendorapi-AGENTS.md): Ready-to-drop-in AGENTS.md file for AI coding agents working on a POS integration of the anybill Vendor API.
- [Vendor API OpenAPI specification (production)](https://vendor.anybill.de/api/swagger/v3/swagger.json): Live OpenAPI 3 document of the production Vendor API; the authoritative schema for every request and response.
- [Vendor API OpenAPI specification (staging)](https://vendor.stg.anybill.de/api/swagger/v3/swagger.json): Live OpenAPI 3 document of the staging Vendor API, where new features appear first.