What is a Human-in-the-Loop?

HITL inserts a mandatory pause into an otherwise automated pipeline. Rather than letting an AI agent send an email, execute a financial transaction, or delete a record autonomously, the system generates a proposed action and holds it for explicit human sign-off — an approval click, an edit, or a rejection — before it's committed. This is distinct from human oversight after the fact; HITL gates the action itself. HITL is the standard mitigation for AI actions that are irreversible, high-stakes, or prone to subtle errors a model can't reliably self-detect — sending customer-facing communication, making a payment, or modifying production data. It costs speed and full autonomy in exchange for a safety net, which is exactly the trade organizations want while trust in a given automation is still being established, or for actions where the cost of a rare mistake far outweighs the cost of a review step.