Human in the Loop
also called HITL
Requiring human review or approval at a defined point in an automated flow, chosen by the reversibility and cost of the action.
The design question is not whether to have a human, it is precisely where. Too many approval points and the automation delivers nothing; too few and an agent takes an irreversible action on bad information.
The workable rule is to gate on reversibility and blast radius. Reading data, drafting, and proposing need no gate. Sending an external communication, moving money, deleting data, or changing production configuration need one. Anything in between should be reviewable after the fact, which requires the action to be logged with enough context to judge it.
Approval fatigue is the failure mode to design against: a human who approves fifty actions an hour approves them all, and the control has become decorative. Batch approvals, present the evidence, and escalate only what is genuinely ambiguous.