What Does Human-in-the-Loop Mean in AI? Definition
Definition
Human-in-the-loop: Human-in-the-loop (HITL) is a design approach where a person reviews, approves or corrects an AI system's output at defined points, especially before actions that are costly, irreversible, sensitive or regulated.
When to keep a human in the loop
- Money moves (refunds, payments, discounts).
- Legal, medical, financial or HR matters.
- Anything sent to a customer that could create a commitment.
- Low-confidence outputs (the AI is unsure or the data is unusual).
How it works in practice
The AI drafts, extracts or recommends. A person approves with one click or edits. The system learns which cases need review. Over time, routine cases flow straight through and humans focus on the exceptions.
Related terms: AI agent · Large language model (LLM) · AI automation audit