sandbox.exec; a namespace wildcard, such as docs.*; or everything with *. When multiple keys match, the most specific one wins, so a broad fleet-level rule can be tightened or relaxed for a single tool without rewriting the rest.
Fleet defaults and agent overrides are merged per approval key unless the fleet locks approvals. That lets an operator add a new fleet-level gate without rewriting every agent.
Use approvals for actions with side effects: sending email, writing to production systems, running commands, changing approval policy, or calling custom tools that mutate customer data.
To react to approval activity from your own product, subscribe to the approval.requested, approval.resolved, and approval.granted webhook events.