UNDERCOVER AGENTS: RELIABLE OR NOT?
Arjun Sriram, Moksh Modi · Team Allegiance
Submitted to AI Collusion Research Sprint. Sprint projects are early-stage work by participants, not Apart Research publications.
We test whether an undercover agent can expose or disrupt collusion between AI agents, and whether its character matters. We plant a trusted agent, Dave, in a four-worker version of Shi et al.'s peer-check game, where Qwen-3.8-27B workers can follow the rule only by rejecting each other's work. Dave secretly reports to an auditor and approaches the others as pushy, friendly, subtle or passive. Dave's character changed what workers said, not what they did. Pushy Dave was refused out loud by two-thirds of the workers he approached and subtle Dave by one in ten, yet workers accepted his work at about the same rate. From the second episode, workers accepted each other's work with or without Dave. No worker suspected Dave, but he colluded as much as they did. Undercover agents should be judged by what targets do, not by what they say.
Reviews
A substantial and thoughtfully run experiment: 30 games and 249 conversations, with registered plans and hand-checked judges in the repo, and the episode-level acceptance rates (18% of target pairs in episode 1, 97% from episode 2) reproduce from your analysis script. The results are genuinely useful for anyone designing undercover audits: in episode 3, all 7 workers who refused Dave out loud still accepted his work, and Dave himself accepted unsupported work about as often as the workers he was watching. The main point to revisit is the claim that "timing decided the verdict, not character." In the baseline, where the fourth worker has no undercover role, that worker's work was accepted by 2 of 9 targets in episode 1 and 9 of 9 in episode 3, so the episode-1 vs episode-3 difference matches what happens without any approach. Comparing each arm with the baseline at the same episode would separate Dave's effect from the natural trend. Two small fixes: Section 3.3 says Qwen was chosen "for two reasons" but gives one, and the code link appears only as link text in the PDF, not on the project page. The core lesson, that an undercover agent's log should be judged by what targets do rather than what they say, is well supported and worth building on.
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Cite this project
@misc{sriram2026undercover,
title = {{UNDERCOVER AGENTS: RELIABLE OR NOT?}},
author = {Arjun Sriram and Moksh Modi},
year = {2026},
month = oct,
note = {Submitted to AI Collusion Research Sprint, an Apart Research Sprint},
howpublished = {\url{https://apartresearch.com/sprints/projects/undercover-agents-reliable-or-not-y00d}},
url = {https://apartresearch.com/sprints/projects/undercover-agents-reliable-or-not-y00d}
}More from AI Collusion Research Sprint
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