Tool Use

In τ-bench retail task 97, a customer named Yusuf Li asks the agent to move a pending order to his New York address and then to "exchange the Bluetooth Speaker in my order for the cheapest green version available." In Sierra's published gpt-4o run (trial 0), the agent changes the address, reads the speaker catalogue, gets the customer's yes, and calls exchange_delivered_order_items on order #W6750959. The order's status, pending, has been in the agent's context since it read the order eight calls earlier. The tool answers Error: non-delivered order cannot be exchanged. The agent tells Yusuf that exchanges only work for delivered orders, he replies "Alright, I'll wait then," and the run ends with a reward of 0. The policy's action for a pending order is modify_pending_order_items, and the same arguments sent to that tool would have completed the task.