@inproceedings{abdurahman-etal-2026-explicit,
    title = "Explicit Trait Inference for Multi-Agent Coordination",
    author = "Abdurahman, Suhaib  and
      Ishii, Etsuko  and
      Margatina, Katerina  and
      Bhargavi, Divya  and
      Sunkara, Monica  and
      Zhang, Yi",
    editor = "Liakata, Maria  and
      Moreira, Viviane P.  and
      Zhang, Jiajun  and
      Jurgens, David",
    booktitle = "Proceedings of the 64th Annual Meeting of the {A}ssociation for {C}omputational {L}inguistics (Volume 1: Long Papers)",
    month = jul,
    year = "2026",
    address = "San Diego, California, United States",
    publisher = "Association for Computational Linguistics",
    url = "https://preview.aclanthology.org/ingest-acl/2026.acl-long.77/",
    pages = "1670--1704",
    ISBN = "979-8-89176-390-6",
    abstract = "LLM-based multi-agent systems (MAS) show promise on complex tasks but remain prone to coordination failures such as goal drift, error cascades, and misaligned behaviors. We propose Explicit Trait Inference (ETI), a psychologically grounded method for improving coordination. ETI enables agents to infer and track partner characteristics along two established psychological dimensions{---}warmth (e.g., trust) and competence (e.g., skill){---}from interaction histories to guide decisions. We evaluate ETI in controlled settings (economic games), where it reduces payoff loss by 45{--}77{\%}, and in more realistic, complex multi-agent settings (MultiAgentBench), where it improves performance by 3{--}29{\%} depending on the scenario and model, relative to a CoT baseline. Additional analysis shows that gains are closely linked to trait inference: ETI profiles predict agents' actions, and informative profiles drive improvements. These results highlight ETI as a lightweight and robust mechanism for improving coordination in diverse multi-agent settings, and provide the first systematic evidence that LLM agents can (i) reliably infer others' traits from interaction histories and (ii) leverage structured awareness of others' traits for coordination."
}