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Introduction
The All Documents API is the central document processing engine of the Biz1 system.
It is designed as a single, unified API layer through which all business documents are created, managed, linked, sent, retrieved, and audited.
Instead of exposing many different APIs for invoices, receipts, orders, and payments, Biz1 provides one powerful API that dynamically adapts its behavior based on parameters—primarily the document_type.
This API supports every business process and every accounting requirement, without forcing external systems to duplicate business
