PACT, head-to-head LLM negotiation benchmark. 20-round buyer-seller bargaining game: each round the AIs can message, the buyer submits a bid and the seller submits an ask. If bid ≥ ask, trade clears at the midpoint. Thousands of matchups.
Summary
PACT introduces a head-to-head negotiation benchmark for LLMs using a 20-round buyer-seller bargaining game to test persuasion and adaptation. Top performers include GPT-5.5 and Opus 4.7, with ratings computed via Glicko-2 on an Elo-like scale.
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