Retrieve a purchase order
Returns the full detail of a single purchase order by UUID or PO number, including all
line items, the vendor account, expected delivery date, receiving history, and the linked
vendor bills. Use ?expand[]=items&expand[]=bills to hydrate nested collections inline.
Requires purchasing:read scope.
Polymorphic path parameter: pass a UUID or a PO number (e.g. PO-001234). If a non-UUID slug is provided it is resolved to the matching purchase order UUID within the entity scope. Returns 404 if no purchase order matches either form.
Authorizations
API key issued per entity via Settings > Developers > API Keys.
Each key carries scopes (e.g. orders:read, products:write).
Bearer token format: Authorization: Bearer ark_live_ent_Test keys use ark_test_ent_. Both are issued per entity
via Settings > Developers > API Keys.
Path Parameters
Purchase order UUID or PO number (e.g. PO-001234). Polymorphic lookup: if the value is not a UUID it is resolved to a UUID via orders.order_number where document_type=purchase_order within the entity scope. (NEW-GAP-API-V1-POLYMORPHIC-LOOKUP-CROSS-RESOURCE 2026-05-20)
Query Parameters
line_items, line_items.product, vendor, receipts, bills Response
Purchase order
A purchase order issued to a vendor.
purchase_order draft, approved, sent, partially_received, received, closed, cancelled The order total as it stood when an approver approved this purchase order -- the basis they actually saw. NULL on every approval predating 2026-08-17 (no backfill) and NULL means "basis unknown", which is treated as fail-safe.
DERIVED, not stored. True when the order is approved AND its total has since risen above approved_total. The purchase order still receives normally; this is a non-blocking prompt to re-approve.
Per-field verdicts for the header fields, from the same predicate the write handlers enforce. Keys: notes, internal_notes, due_date, expected_date, location_id, po_tracking_reference. Each is { allowed: boolean, reason: string|null } where reason is a token from the PoLineEditReason vocabulary.

