How is it different from an approval workflow?

Human-in-the-loop is the principle. An approval workflow is the implementation: a specific checkpoint, a named reviewer and a decision that releases the action.

Does keeping a person in the loop make the system slower?

It adds a decision, not the work. The agent has already completed the task, so the human cost is a judgment rather than an execution.

Human-in-the-Loop

Human-in-the-loop is a workflow in which a person reviews or approves an AI system’s output before it takes effect.

The phrase covers a spectrum. At one end a person checks everything, which is safe and removes most of the benefit. At the other, a person is notified afterwards, which is fast and is not really review. The useful versions sit in between: the AI does the whole job, and a person makes a decision at the points where being wrong would be expensive.

What makes it work in practice is the quality of what arrives for review. A reviewer handed a finished draft with the reasoning and the sources attached can make a judgment in seconds. A reviewer handed a request to approve an opaque action will either rubber-stamp it or stop using the system, and both outcomes defeat the purpose.

Frequently Asked Questions

No, and doing so usually removes the benefit. The point is to place review where a mistake would be costly, not to re-do the work uniformly.