POST /Invoices/{id}/items

Existing line-item id, sent on update so the line is reconciled in place (id + any linked inventory transactions preserved) instead of being dropped and recreated. Null/empty for a brand-new line.

Source BillableItem ("Charge") when this line was added from the charge catalog.

Flat-rate metadata round-tripped by the invoice grid (Quantity is the billed 1). Null leaves a line's stored values alone, so an older client can't clear them.

The pet this line is for, on a combined multi-pet bill (ITE-1157). Null means "leave as is" — never "clear" — so callers that predate the field change nothing. Changing an existing line's pet is refused for dispensed and plan-benefit lines.

Source BillableItem ("Charge") when this line was added from the charge catalog.

Display name of the source BillableItem (snapshot, response-only).

True when a BillableItem charge line has been fulfilled — its inventory components dispensed (derived from linked transactions, response-only).

Flat-rate inventory line: billed as one administration whatever amount was given.

Audit: who last set a manual discount on this line, and when.

Kit this line came from, when emitted via GroupCode expansion.

Snapshot of the kit's display name at time of add.

Which add of the kit this line came from (shared by that add's lines). Server-owned and read-only, like string? InvoiceLineItemDto.SectionKey: invoice saves never write it.

The estimate line group this line was billed under (EstimateLineGroups), snapshotted at convert; null when ungrouped or added to the bill directly. Read-only: invoice saves ignore it. List<InvoiceLineItemDto> InvoiceDto.Items already comes in section order.

Heading of string? InvoiceLineItemDto.SectionKey's section.

The pet this line is attributed to on a combined multi-pet bill (ITE-1157) — the resolved attribution, not the raw column. Set only on bills that carry patientShares; null there means no pet could be resolved.

True when the line's pet can't be changed: it was dispensed for a pet, or a pet's plan benefit paid for it. The pet comes from that record.

Why bool InvoiceLineItemDto.PatientIdLocked is set, for the UI's tooltip.