An order is in the queue when it is pending or partly fulfilled, not canceled, not hidden from the queue, not escalated, has no shipment confirmation in flight and was created within a year, and when it has either no fulfillment order (mode direct) or at least one shippable one (tenant-portal, pending or partly fulfilled, open or in progress). Priority first, then oldest first (order=newest flips the second key). warehouseId matches the order ship-from warehouse, or an order with no warehouse of its own whose shippable fulfillment order sits at that warehouse. A caller bound to channels sees only its channels.

Scope: channel:read, channel:write, fulfillment:write, shipments:write or admin. A permission group made before the Channel API scopes existed grants it as fulfillment-orders:manage.

Idempotency: not keyed; the request itself is safe to repeat.

Rate limit: read class, 6,000 requests per minute per tenant by default (write class 1,200). Every response carries X-RateLimit-Limit, X-RateLimit-Remaining and X-RateLimit-Reset; a refusal is 429 rate_limited with Retry-After.