• Format XML, encoding UTF-8, transport HTTPS, access POST
• The interface is passive; the response is synchronous XML
• Document numbers are integer (max 2147483647)
• The whole XML post size limit is 19 MB; attachments are unlimited in count but must all fit within it.

• Input creates a new document or updates an existing one (matched by external key / number).
• To modify, the component must have xd_update=1; on update, post the whole document (it is overwritten).
• A confirmed document cannot be modified – response Type=14 (confirmed or has linked documents). Exception: xd_updateconfirmed=1 allows modifying a confirmed document for order, invoice, purchaseorder, stockreceipt.
• Exception: a delivery document cannot be modified.
• Partial modification applies only to partner master data: xd_customer_update=1 / xd_supplier_update=1 updates an existing customer/supplier name, email and phone (response 30 Updated). Transaction documents cannot be partially modified.
• Behaviour is controlled by transport parameters; some inputs also support default value setup.

An exception, not default functionality. If needed, a custom after-save processing step can be added to the interface (by agreement with Directo) – extra logic that runs after the document is saved. Unlike transport parameters, this is not a standard setting but a case-by-case extension.