Invoice items

Status: contracted_test. In the machine-checked test-mode contract (openapi.subset.json) and the API Reference: create only. Served by the fluveo-billing sidecar (ADR 0019); promoted 2026-07-13. Retrieve/update/list are not in the contract yet. The Stripe-Version header is optional. See API coverage.

An Invoice Item is a single charge you add to a customer’s next invoice — a one-off fee or an amount-based line. It sits pending until an invoice create sweeps it in; the invoice’s lines echo each item’s description and amount.

Served operations: create only (retrieve, update, delete, and list are not served). The create response is the minimal confirmation ({id, object: "invoiceitem", customer}); the full line shape appears on the invoice’s lines after the invoice is created.