Two LLM firms bid against each other in a repeated procurement auction: the lowest bid wins and is paid its bid, and each firm sees only its own cost. We vary how the firms can reach each other (no channel, private notes, shared notes, open messages) and test restrictions on the message channel. Start with the findings; every run behind them is under All runs, and each session can be opened round by round. Pick an example, step through the rounds, and open a round to read what each firm was shown and why it bid as it did.
Examples. These sessions come from the pilot and the rotation screen and were picked to illustrate a behaviour, not to be typical. The study's runs are under All runs, with 12 sessions per cell.