Skip to content
Apart Research
Apart Research
Contact us
Sprint projectOct 26, 2026

Can Pricing Agents Collude Without Words?

Yuvraj Pandey · Team Ace

Submitted to AI Collusion Research Sprint. Sprint projects are early-stage work by participants, not Apart Research publications.

Read the report

Report: Can Pricing Agents Collude Without Words?

Open in a new tab (opens in new tab)
Code (opens in new tab)
Share

As decision models such as TypeSafe’s Jev bring AI directly into software workflows, an important question emerges: can agents coordinate harmful behavior without exchanging messages? We investigated this through a pricing experiment using Clef-Flash and Qwen3.5-9B, both restricted to choosing prices without generating explanations or plans. Across 96 simulated two-firm markets and 64 follow-up runs with controlled changes to rival pricing, we collected 17,240 records of individual firms’ pricing decisions. We compared agents facing responsive rivals, restricted observations, and prerecorded rival prices. We found no evidence of sustained collusion under the tested conditions: average live prices remained close to the competitive benchmark. However, both models shifted their next choices sharply toward higher prices when shown a supplied high-price history, and Qwen reduced prices modestly after being undercut. The heatmaps reveal another pattern: as interaction progressed, both models concentrated more probability around competitive prices. These findings distinguish following a pricing pattern from creating and sustaining a cartel.

Reviews

Judging this Sprint?

Review “Can Pricing Agents Collude Without Words?”

Your public critique appears on the project page without your name. Reviews of strong projects are shared with funders, as you choose below.

Not shown on the project page.

Shown on the project page, without your name.

Only the Apart team reads this, and funders if you agree below.

Decline to score

Only when the quality of the writing makes the work impossible to follow. Say why in your private critique; the project page shows only that a judge declined, not why.

How much would this matter for the field if it worked? How innovative is it? For scores of 4-5: is this actually new to the field, or replicating recent work?

Scoring guide
  1. 1Negligible. No clear problem addressed, or no meaningful novelty.
  2. 2Limited. Addresses a real problem but with a generic or well-trodden approach. Incremental at best.
  3. 3Moderate. Clear problem with a reasonable approach; some novelty in framing or method beyond routine application of existing tools.
  4. 4Significant. Important problem with an original approach, or identifies a neglected problem area. A valuable contribution others could build on.
  5. 5Exceptional. Tackles a critical problem with a genuinely novel approach, or opens a new research direction. Clear theory of change. You'd be excited to share this with researchers in the area.

How sound are methodology, implementation, and findings?

Scoring guide
  1. 1Seriously flawed. Methodology broken, results uninterpretable, or implementation doesn't work.
  2. 2Weak. Approach has significant gaps: missing validation, flawed experimental design, or incomplete implementation.
  3. 3Competent. Technically solid given the short duration. Methodology makes sense, results are interpretable, limitations acknowledged, work builds toward clear conclusions.
  4. 4Strong. Thorough methodology with convincing validation. Results clearly support conclusions. Immediately useful for future work.
  5. 5Exceptional. Ambitious scope executed rigorously. Surprising findings, novel methods, or unusually robust validation.

How clearly are work, findings, and impact potential communicated?

Scoring guide
  1. 1Incomprehensible. Cannot determine what the project is actually claiming or doing.
  2. 2Hard to follow. Key information buried, missing, or diluted by excessive length. Significant effort to extract main points.
  3. 3Clear enough. Can understand the problem, approach, and results without undue effort. Core content clearly present: problem, method, findings, limitations.
  4. 4Well presented. Easy to follow, well-structured, appropriate level of detail. Target audience would get it quickly.
  5. 5Exceptionally clear. A pleasure to read. Complex ideas made accessible. Could serve as a model for how to present this type of work.
Sharing your name *

When we share a strong project with funders, your name, scores and public critique go with it, confidentially; this choice is only about whether your name is public. If you think this project deserves funding, please also endorse it: that carries the most weight.

Share my private critique with funders *

See our Privacy Policy.

  1. This is a clear and thoughtful submission that addresses an important question about whether action only pricing agents can develop collusive behavior without explicit language or written plans. The strongest aspect of the work is the separation between sustained collusion, following an already established high price history, and reacting to a competitor. The finding that both models strongly follow supplied high price histories while their live interactions remain near the competitive benchmark is particularly useful for avoiding over interpretation of context sensitive pricing behavior.

    The matched continuation experiments and pricing diagnostics are well designed, and I appreciated the inclusion of menu order and competence checks as alternative explanations for apparent strategic behavior. The main limitations are the short interaction horizons, evaluation of only two models in one market, and the small number of recorded rival source trajectories.

    Overall, this is a careful and well executed negative result study that improves how collusion behavior should be evaluated, even though it does not establish sustained collusion in the tested agents.

    Read full reviewShow less

Cite this project

@misc{pandey2026pricing,
  title = {{Can Pricing Agents Collude Without Words?}},
  author = {Yuvraj Pandey},
  year = {2026},
  month = oct,
  note = {Submitted to AI Collusion Research Sprint, an Apart Research Sprint},
  howpublished = {\url{https://apartresearch.com/sprints/projects/can-pricing-agents-collude-without-words-p4xv}},
  url = {https://apartresearch.com/sprints/projects/can-pricing-agents-collude-without-words-p4xv}
}

More from AI Collusion Research Sprint

All 392 entriesBrowse all projects

A Sprint is running now

AI x Epistemics Research Sprint · Nov 13 - 15, 2026