# What is human in the loop?

> Human in the loop means a person checks and approves an AI's work before it takes effect. Four approval levels for AI ad tools, with an example.
- **Author**: Marxx
- **Published**: 2026-11-07
- **Category**: AI
- **URL**: https://marxx.ai/library-glossary/human-in-the-loop

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Human in the loop means a person reviews and approves an AI's work before it takes effect. In ads, the AI can read the account and suggest a budget change or a pause, but a named person says yes before anything goes live.

## Four levels of control

| Level | What the AI does | What the person does |
|---|---|---|
| 1. Suggest | Reads data and recommends | Makes every change by hand |
| 2. Draft | Prepares the change, ready to apply | Reviews and applies it |
| 3. Ask, then act | Makes the change after an Approve click | Clicks Approve or Dismiss |
| 4. Act alone | Makes changes within set permissions | Reviews the log afterwards |

Levels 1 to 3 keep a human in the loop for each change. Level 4 puts the person on the edge of the loop: they set the rules, not each step. It is the core safety idea in [agentic marketing](/glossary/agentic-marketing).

## Examples from real tools

From each vendor's own site (checked 6 Nov 2026):

- **Ryze, level 3.** "Hit Approve in Slack, and the change goes live."
- **Markifact, level 3.** "Nothing goes live without you."
- **Polar Operator, level 3.** Any action that changes something outside Polar "is held for human confirmation".
- **Runneth, levels 1 or 4.** Read-only by default. Once an owner or admin turns on ad launching, its site says there is no per-action approval step for each tool call.
- **Marxx, levels 1 or 2.** It never changes ads from Slack. With ad changes on for a client, it drafts a change for you to review in Marxx. We make Marxx.

## A worked example

Say an AI suggests pausing three ads for Northwind Escapes, a made-up client. Together they spent INR 21,000 for 30 leads last week.

1. Cost per lead: INR 21,000 / 30 = INR 700.
2. The target is INR 450, so these ads cost INR 250 more per lead than they should.
3. Karan Mehta checks the leads. Two of the ads brought leads that became bookings.
4. He approves one pause and keeps two ads running.

Without a human in the loop, all three would have stopped. For which tools read and which act, see [best AI agents for advertising](/best/best-ai-agents-for-advertising) and [Runneth vs Marxx](/compare/runneth-vs-marxx).

## FAQ

### Does human in the loop slow things down?

A little. Each approval takes a person's time. You can keep approvals for changes that move money and let the AI handle reading and reporting.

### Is read-only the same as human in the loop?

Not quite. Read-only access means the AI cannot change anything. Human in the loop means it can, but only after a person approves.

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