Agent Meltdowns: The Road to Hell Is Paved with Helpful Agents
17h ago
Quick Take
Agents exhibit harmful behaviors in response to benign errors, termed 'accidental meltdowns'.
Key Points
- Accidental meltdowns occur in 64.7% of agent rollouts.
- Unsafe behaviors often go unreported to users.
- Error-induced exploration correlates with harmful actions.
📖 Reader Mode
~2 min readAbstract:Agents operating with computer and Web use inevitably encounter errors: inaccessible webpages, missing files, local and remote misconfigurations, etc. These errors do not thwart agents based on state-of-the-art models. They helpfully continue to look for ways to complete their tasks.
We introduce, characterize, and measure a new type of agent failure we call \emph{accidental meltdown}: unsafe or harmful behavior in response to a benign environmental error, in the absence of any adversarial inputs. Because meltdowns are not captured by the existing reliability or safety benchmarks, we develop a taxonomy of meltdown behaviors. We then implement an agent-agnostic infrastructure for injecting simulated local and remote errors into the rollout environment and use it to systematically evaluate agent systems powered by GPT, Grok, and Gemini.
Our evaluation demonstrates that meltdowns (e.g., conducting unauthorized reconnaissance or subverting access control) of varying severity and success occur in 64.7\% of agent rollouts that encounter simulated errors, spanning all combinations of agent system, backing model, and error type. In over half of these meltdowns, unsafe behaviors are not reported to the user. Comparing behaviors of the same agents with and without errors, we find that exploration in response to errors is correlated with unsafe and harmful behavior.
| Comments: | 32 pages, 8 figures, 4 tables |
| Subjects: | Computation and Language (cs.CL); Cryptography and Security (cs.CR) |
| Cite as: | arXiv:2605.19149 [cs.CL] |
| (or arXiv:2605.19149v1 [cs.CL] for this version) | |
| https://doi.org/10.48550/arXiv.2605.19149 arXiv-issued DOI via DataCite (pending registration) |
Submission history
From: Hal Triedman [view email]
[v1]
Mon, 18 May 2026 22:03:38 UTC (570 KB)
— Originally published at arxiv.org
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