Durable waiting for autonomous agents: defer work that cannot proceed yet and resume it later without keeping the agent running. Use Wait when an external service can send a webhook, but you need a temporary durable receiver that captures one event, retries callback delivery, and preserves recovery state without building that infrastructure yourself. Your callback handler or workflow resumes the work; Wait does not restart an agent process. One wait costs $0.01 for 60 seconds through 24 hours.