Part 5 of 7 · 4 min read

Machine-to-Machine: When AI Codes for AI Without Human Supervision

What happens when humans leave the daily loop, and where we must draw the "Thermostat Line."

By Markus van Kempen · October 2026

Cartoon: two robots at desks pass a checked document and talk in code while a person walks out of the door.

In Part 4, people stayed in control by standing at both ends of the loop: setting the goal at the start and owning the outcome at the finish. An honest look ahead has to test that. What happens on the day people step out of the loop entirely?

The loop without people

In April 2011, a researcher in Michael Eisen's lab at UC Berkeley went to buy an old biology textbook on Amazon, The Making of a Fly. The two new copies were listed at $1.7 million and $2.2 million. The next day, both prices were higher. Two sellers had each handed their pricing to a bot. One always priced its copy just below the other. The other always priced its copy 27 percent above the first. The bots answered each other every day, and for days nobody at either shop noticed. The price peaked at $23,698,655.93, plus $3.99 shipping.

Neither bot was broken. Each did exactly what it was told. Together they were absurd, and it took a person who actually wanted the book to notice. That was two simple rules in 2011. Now picture two agents that write their own code.

In Part 1, one agent asked for code and another one wrote it. Now take the person out of the rest of the loop: the review, the merge and the deploy. You can wire that up today. A coding assistant opens a pull request on GitHub. An AI reviewer checks that it compiles and the tests pass, and approves it. The pipeline merges and deploys. Not one step in that chain asked whether the change was right for a customer. That isn't a bug. That is the pipeline working as designed.

A flow from issue, to an AI agent writing the fix, to a pull request, to an AI tool reviewing it, to merged and shipped. A person may look at the end, or not at all.

The MCP servers I build make this easier on purpose: any agent can find a tool and use it, so one agent's helper can gain a second client it never knew about, and break it with the next change. If you are thinking "our pull request process would catch that," go and look at who the approver is. Is it a person, or just a name on a list?

The easier we make our tools for AI to operate, including the signposts from Part 2, the faster this loop closes on its own. If machines building for machines becomes the norm, with people as occasional guests, here is what I expect:

Drawing the "Thermostat Line"

I don't think that future is all bad. Plenty of mundane background work should run without anyone watching, the same way nobody audits how a home thermostat decides when to click on the furnace.

The real challenge is separating "thermostat work" from work that affects a person's life or wallet, especially when both live inside the very same system.

A line from work machines can run on their own, like a thermostat, to work that decides something about a person, which a human must own.

That is the first and most important boundary for any autonomous system: keep people in charge of what affects people.

What does that look like in code? "Keep people in charge of what affects people" doesn't help anyone on a Tuesday afternoon unless you can type it. So make the pipeline look at what a change touches. If it reaches an endpoint or a table that handles money, access, or a support request, it is blocked until a named person signs off. Don't rely on a tag the agent has to remember to add. An agent rewarded for fast merges has every reason to leave it off. The default is blocked, and only a human can open it.

How much of your team's workflow is "thermostat work" that you'd happily never look at again, and where is the exact line where a human must step in? Let me know on LinkedIn.

Cheers,
Markus

No bug 🐛 too small, no syntax too weird 🔍 🧐 🔨 🦾

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