Build a procurement approval workflow: agent drafts a purchase order, human approves, agent executes

Steps

1. The agent researches the purchase and assembles a structured purchase order draft: vendor name, item descriptions, quantities, unit prices, total amount, business justification, and the vendor's payment method or checkout URL.
2. The agent submits the PO draft to a review queue with a status of pending_approval; it does not contact the vendor or initiate payment at this stage.
3. The human approver reviews the PO in a structured UI that shows the draft alongside comparable pricing data if available; the approver can approve, reject, or request modification.
4. On approval, the system generates a scoped payment authorization token bound to the PO ID, vendor, and approved amount; this token is passed to the agent to execute the purchase.
5. The agent executes the purchase using only the scoped token; if the actual checkout total differs from the approved PO total (by more than a small tolerance, e.g., 2%), the agent must halt and re-queue for approval rather than proceeding.
6. After purchase, the agent captures the vendor's order confirmation and receipt, links them to the PO record, and closes the PO as fulfilled; the full PO lifecycle (draft, approved, executed, fulfilled) is stored in the audit log.