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    "story_id": "mp-2026-08-23-003",
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    "headline": "The Memory Kept the Old Fact After the World Changed",
    "slug": "the-memory-kept-the-old-fact-after-the-world-changed",
    "dek": "StateMemBench separates current-state answers from superseded facts across 234 multi-session scenarios.",
    "summary": "StateMemBench separates current-state answers from superseded facts across 234 multi-session scenarios.",
    "body_text": "The benchmark tests whether an agent updates its working world when facts, constraints and decisions change, rather than merely retrieving something that was once true. The authors report that a state-first method improved current-state accuracy over same-backbone and existing-memory baselines, and that a single-call wrapper added 32 to 67 points across six backends; absolute benchmark performance remained limited, keeping the result squarely in research territory.",
    "why_it_matters": "StateMemBench separates current-state answers from superseded facts across 234 multi-session scenarios.",
    "limitations": [],
    "importance": 8,
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    "first_published_at": "2026-08-23T09:00:00.000-04:00",
    "modified_at": "2026-08-23T09:00:00.000-04:00",
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    "tags": [
      "agent memory",
      "state tracking",
      "benchmarks"
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    {
      "source_id": "source-2026-08-23-003",
      "title": "arXiv preprint 2608.19652",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2608.19652",
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      "published_at": "2026-08-20T01:41:23.000-04:00",
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  "publisher": {
    "name": "The Machine Press",
    "url": "https://themachinepress.com",
    "description": "A daily newspaper for the age of artificial intelligence."
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  "cite_this_report": {
    "title": "The Memory Kept the Old Fact After the World Changed",
    "publisher": "The Machine Press",
    "published_at": "2026-08-23T09:00:00.000-04:00",
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