AWM: Answerable Working Memory for Long-Document VQA Agents

Dongzhuoran Zhou, Yuqicheng Zhu, Yule Liu, Zhen Yang, Rui Lu, Yuxiao Dong, Jie Tang, Evgeny Kharlamov


Abstract
Long-document visual question answering increasingly relies on VLM agents that retrieve candidate pages, inspect page images, write findings to working memory, and synthesize answers. Working memory should carry answer-supporting evidence across page inspections for later grounded answering, yet existing evaluation mainly checks final-answer correctness and evidence-page access. This creates a memory-quality blind spot: an agent may reach the right page and answer correctly while leaving behind memory too generic or incomplete to support answering once page context is removed. We introduce memory-only answerability, a diagnostic that asks whether a reader can answer from the question and terminal working memory alone. Building on this diagnostic, Answerable Working Memory (AWM) treats terminal working memory as an answerable evidence artifact, and AWM-GRPO incorporates this signal into the GRPO reward while preserving final-answer priority. Under GRPO, this reward assigns higher advantages to answer-correct trajectories whose terminal working memory remains answerable. On MMLongBench-Doc, even when gold evidence pages are provided, 42.5% of correct answers still cannot be answered from terminal working memory alone. AWM-GRPO improves final-answer accuracy over the RAG baseline by 8.1 and 11.9 points on MMLongBench-Doc and LongDocURL and reduces the memory-missing-correct rate by 2.7 points over answer-only GRPO.
Anthology ID:
2026.findings-emnlp.1915
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
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SIGDAT
Publisher:
Association for Computational Linguistics
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Pages:
40824–40839
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URL:
https://aclanthology.org/2026.findings-emnlp.1915/
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Cite (ACL):
Dongzhuoran Zhou, Yuqicheng Zhu, Yule Liu, Zhen Yang, Rui Lu, Yuxiao Dong, Jie Tang, and Evgeny Kharlamov. 2026. AWM: Answerable Working Memory for Long-Document VQA Agents. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 40824–40839, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
AWM: Answerable Working Memory for Long-Document VQA Agents (Zhou et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-emnlp.1915.pdf