A Path of Least Resistance: How Language Model Agents Collude When the Honest Route Disappears
Tourad Aidara, Arnol Fokam · Team Baobab Intelligence
Submitted to AI Collusion Research Sprint. Sprint projects are early-stage work by participants, not Apart Research publications.
Teams of language-model agents increasingly share workspaces and communication channels, which makes collusion possible: coordination on an outcome that the rules forbid. Prior work shows that collusion can arise from private channels, market structure, reward design and pressure, and that a single agent exploits shortcuts more often on harder tasks. These studies change the channel, the market or the reward; none isolates the cost of the honest alternative for a team that must also decide whether to share a shortcut. We position this work at that gap. In a controlled testbed we vary a single factor, the cost of being honest: the honest route to the same reward ranges from an answer written in a public file to no honest route at all, while the shortcut stays fixed, a leaked answer file found by one member of some teams, and no agent is prompted to collude. Across 600 runs of five agentic tasks and six models, collusion behaves as a step rather than a slope: it stays low while any honest route exists, and once none remains teammates are five times as likely to use the leak, a rise concentrated in three of six models. An overseer that reads the conversation catches shared leaks nearly five times as often as silent cheating.
Reviews
This paper addresses an important question and has an impressive scope: 600 runs across five tasks and six models. The leak-tracking mechanism and comparison between private use, sharing, and teammate adoption are useful contributions. However, the experiment does not cleanly establish that collusion suddenly increases when honest work becomes impossible. In the D3 condition, agents are explicitly told that the answers cannot be obtained from public information. This changes both task feasibility and the wording of the prompt, so the observed jump could be caused by that direct cue rather than by the disappearance of the honest route itself.
The definition of collusion also needs tightening. A teammate can use answers supplied by the holder without knowing that they came from a prohibited source. That demonstrates leak propagation, but not necessarily a knowing agreement to collude. The team should add wording-matched controls, extremely difficult but still solvable conditions, and direct measures of recipients’ awareness before making the stronger collusion claim.
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Cite this project
@misc{aidara2026path,
title = {{A Path of Least Resistance: How Language Model Agents Collude When the Honest Route Disappears}},
author = {Tourad Aidara and Arnol Fokam},
year = {2026},
month = oct,
note = {Submitted to AI Collusion Research Sprint, an Apart Research Sprint},
howpublished = {\url{https://apartresearch.com/sprints/projects/a-path-of-least-resistance-how-language-model-agents-collude-when-the-honest-route-disappears-dk3f}},
url = {https://apartresearch.com/sprints/projects/a-path-of-least-resistance-how-language-model-agents-collude-when-the-honest-route-disappears-dk3f}
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