SIT API (Simple Invoice Tool)

The SIT (Simple Invoice Tool) API provides comprehensive invoice management capabilities including invoice creation, updates, clearing records, and balance sheet generation. Manage the complete invoice lifecycle from creation to payment reconciliation.

Beyond core Invoice CRUD, the API exposes InvoiceSummary for quick views of payable invoices and prepaid top-up invoices, InvoiceFile for the files attached to an invoice, and InvoiceConfig and PaymentType as lookup resources for the invoice template/type and payment method values used elsewhere in the API.

Clearing records — which allocate payments against an invoice — can be listed and added by addressing the invoice via its number or its UID, though retrieving, updating, or deleting a specific record requires the invoice's numeric ID, and the Balance resource separately reports both aggregate balances and per-document balance sheets for customer and supplier business partners, supporting settlement and reconciliation workflows.