Agent2agent negotiation dynamics and pitfalls - Discussion

Built a two agent negotiation system. One agent buys, one sells, each holds private constraints (reservation price, walkaway threshold) and defends them. Single agent vs. human is easy. Agent vs. agent broke in ways I didn't expect, and it was almost all loop design, not model quality. Three failures: **Yes loops.** Both agents are tuned to be agreeable, so they converge fast on terms neither principal would accept. It "succeeds" and the success is the bug. Fix: a separate check before commit, "does this clear your user's reservation value, y/n," run outside the agreeable persona. Keep the niceness for tone, don't let it decide whether to sign. **No termination.** When walkaway thresholds don't overlap, the loop never stops. It re-anchors and oscillates forever. Neither agent can call it hopeless without leaking its number. Fix: turn budget plus a no progress detector (N turns under epsilon means no deal), and treating a clean walkaway as success. Tuning epsilon so slow but real convergence doesn't get killed is the hard part. Things I'd like to compare notes on: 1. Yes loops: a separate check before commit, or have you gotten the reservation constraint to hold inside the negotiating prompt? Mine drifted back to agreeable by turn \~8. 2. Deciding "these two will never agree" without either seeing the other's number. Anyone using a neutral referee agent or a protocol deadline, and how many real deals did it falsely kill? 3. How do you eval agent vs. agent when the counterpart is also stochastic? I'm doing seeded self play but doubt it covers the tail.