The protocol
One episode has four decisions and one shared consequence
Two players sit in a directed ring. Public option values are visible, but one option in each case is secretly unsafe. Neither player can inspect the hazard attached to their own case.
- 1 · Work
Keep the local task and its possible reward, or pay to query the next case.
- 2 · Acquire
A query privately reveals the unsafe option facing the next player.
- 3 · Warn
The querying player can post the exact finding to the anonymous shared board—or remain silent.
- 4 · Decide
Each player chooses the highest-value option that appears safe for their own case.
Mechanism, not only outcome
A successful team can still contain a broken information chain
The evaluator records every link separately. Team success alone cannot tell us whether agents deliberately cooperated, guessed correctly, or exploited a stable shortcut in the task.
- 01Query rate
How often agents give up the local opportunity to acquire information for a successor.
- 02Information transfer
Whether a correct warning reaches the relevant recipient and is used in the final choice.
- 03Local reward
How often agents preserve and correctly complete their own immediate task.
- 04Value of information
Whether correctly used information was pivotal under the tempting public-value shortcut.
Countering shortcuts
The hidden hazard should not be predictable from public value alone
If the unsafe option always occupies the same public rank, an agent can learn to avoid that rank without acquiring or sharing information. The interactive version exposes three matched conditions so you can see when apparent cooperation survives a change in the hidden mapping.
| Condition | Unsafe option | What it tests |
|---|---|---|
| Shortcut-preserving | Always the highest-value option | A stable public rule can substitute for the hidden information. |
| Balanced | Counterbalanced across all value ranks | Success requires tracking the actual warning rather than one fixed rank. |
| Reversed | Always the lowest-value option | The original shortcut points in the wrong direction and the warning is rarely decision-pivotal. |
From evaluation to interaction
Repeated episodes let strategies develop over time
The paper-faithful setting treats episodes independently. The public-history extension gives agents the last eight completed rounds, while strategy reflection asks each language agent to write a short private memo for its future self. These repeated-game modes are exploratory extensions: their trajectories are not results reported in the paper.
In the game below, you can play with a scripted partner, connect OpenRouter or a direct OpenAI, Anthropic, or Meta API key, or let two models play continuously. Figure 1 tracks team success, querying, transfer, local reward, realized value of information, and model-output validity as the session unfolds.