"They operate like slot machines": AI agents are scrambling power users' brains

A growing number of software developers say AI coding tools are frying their brains.

The big picture: The most popular agentic AI systems have triggered something that looks a lot like addiction among some of tech's highest performers.

Catch up quick: Agentic coding tools like Anthropic's Claude Code, OpenAI's Codex and the open-source tool OpenClaw can write, test and ship software autonomously.

• The developer prompts, watches, reviews and then prompts again.
• It sounds great. Until it isn't.

What they're saying: OpenAI co-founder Andrej Karpathy — coiner of the term "vibe coding" — told the "No Priors" podcast he's been in a "state of AI psychosis" since December, trying to figure out what's possible and "pushing it to the limit."

• Karpathy says his ratio of hand-written to AI-delegated code flipped from 80/20 to 0/100 in December.
• He now spends 16 hours a day issuing commands to agent swarms.
• Karpathy pays a monthly subscription fee and when he has tokens left over near the end of the month he says he "feel[s] extremely nervous" and rushes to exhaust his supply in order to keep up with everyone else.

Y Combinator CEO Garry Tan has called his experience grinding with coding tools "cyber psychosis" and posted in January that he "stayed up 19 hours yesterday and didn't sleep til 5AM."

• In response to a startup founder bragging that his CTO hadn't slept in 36 hours, Tan said: "This is unhealthy by the way (speaking from experience)."

AI developer and blogger Simon Willison, who has 25 years of pre-AI coding experience, said on "Lenny's Podcast": "There is a limit on human cognition, in how much you can hold in your head at one time. And it's very easy to pop that stack at the moment."

• Developers need to know their own limits and figure out responsible ways to prevent burnout, he says. Choosing agentic coding over sleep is "obviously unsustainable."

Allen Institute for Artificial Intelligence research scientist and assistant professor at Carnegie Mellon University Tim Dettmers says peak productivity comes from working with as many agents as possible in parallel, and that requires near-constant context switching, which humans aren't great at.

• "Part of the draw is that agents expand what feels possible, but at the same time they really amplify this ongoing tension around focus and mental bandwidth," Dettmers tells Axios.

The intrigue: Work with agentic coding tools is starting to look less like a fun quirk and more like a pathology.

• There are elements of gambling and addiction in the way people are using these tools, Willison said on "Lenny's Podcast."
• "Many of us got hit by the agent coding addiction. It feels good, we barely sleep, we build amazing things," software developer Armin Ronacher wrote in January.

Between the lines: Researchers from Boston Consulting Group and UC Riverside call the phenomenon "brain fry:" mental fatigue from excessive use or oversight of AI tools beyond one's cognitive capacity.

• Their study published in Harvard Business Review found that "AI-associated mental strain carries significant costs in the form of increased employee errors, decision fatigue, and intention to quit."
• Companies view token use as a sign of productivity, according to Harvard Business Review.

Reality check: Serious coders have always been "locked in" to meet deadlines, and pulling all-nighters is nothing new.

• Elon Musk and his crews have been sleeping at the office and on factory floors for years, but at least they slept.

Zoom in: Quentin Rousseau, CTO and co-founder of the incident management platform Rootly, told Axios he couldn't sleep for months after switching to agentic coding. Eventually he needed a doctor to prescribe sleep medication just to shut his brain off at night.

• Rousseau calls himself an AI accelerationist, but warns that people need to use agentic tools carefully because they're designed to be addictive.
• "They operate like slot machines," he said. "You hit one prompt, you get an answer, you get some coding done." But then, Rousseau says, sometimes the agent will fail miserably.
• He added that founders are, "by default," more addicted to these productivity tools. "We're probably the first people to be collateral of these systems," he told Axios.

What we're watching: If software developers are a bellwether for AI burnout, brain fry could be coming for us all.