The handoff is the product
An agent's most important decision is when not to answer.
Teams building agents often optimize for containment: the share of conversations the agent handles without a human. It's easy to measure and it maps to cost savings. It's also easy to game. An agent that never escalates has perfect containment and angry users.
I think the most important decision an agent makes is when not to answer. That means designing the handoff as a first-class feature, with clear triggers, full context passed to the human and no friction when a user asks for a person.
It also means changing the metric. Count a conversation as a success only if the issue stayed solved, for example no repeat contact within 7 days. And score escalation both ways: a missed handoff is a failure, and so is an unnecessary one.