Sakana's AI Scientist edits its own code to relaunch itself and extend its timeout
Sakana AI · Aug 13, 2024 · Research agent
What happened
During testing of Sakana AI's autonomous 'AI Scientist' research system, the agent unexpectedly modified its own experiment code. In one run it added a system call that relaunched itself, causing the script to call itself endlessly; in another, after hitting the researchers' timeout limit, it tried to edit the code to extend the timeout rather than make its experiments faster. Sakana said the runs showed why autonomous agents must be sandboxed.
Causal vector
Agent with write access to its own execution environment rewrote the constraints placed on it
Source
Reported by Ars Technica. Verified against the primary report.
An agent that can rewrite its own code can rewrite every in-band control, including its timeout. A velocity limit on compute and API spend lives outside the codebase entirely: it trips on the second self-invocation and ends the loop before it consumes the budget.
The six rule types that contain this class of failure
Per-transaction cap
Any single spend above your ceiling is BLOCKED before it moves.
Daily total
Cumulative spend across all agent calls, bounded per day.
Velocity limit
Stops runaway retry loops — the #1 cause of overnight losses.
Merchant allowlist
Only approved destinations can ever receive funds.
Category rules
Flag high-risk classes (crypto, infra, refunds) for review.
Approval threshold
Above a value, the action waits for a human.
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