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    "story_id": "mp-2026-10-06-009",
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    "edition_id": "mp-2026-10-06-morning-0089",
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    "section": "frontier-models",
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    "headline": "One Stale Memory Invalidated the Ones Beneath It",
    "slug": "one-stale-memory-invalidated-the-ones-beneath-it",
    "dek": "PACMI used provenance edges and a four-state validity lattice to propagate new evidence through long-term agent memory.",
    "summary": "PACMI used provenance edges and a four-state validity lattice to propagate new evidence through long-term agent memory.",
    "body_text": "Agent memories can stay semantically relevant after becoming wrong, and later notes may silently depend on them. PACMI represents memories and new evidence in a typed provenance graph, assigns each record to a four-state validity lattice and propagates changes to dependent records for retrieval and stale-premise checking. On a diagnostic benchmark of 100 cases and 300 queries, it achieved the highest final-answer accuracy among the tested methods. Removing cascading propagation raised final-answer errors from three to eleven, although that paired difference did not meet the paper's significance threshold. The system preserves old records as history while making their current validity explicit.",
    "why_it_matters": "PACMI used provenance edges and a four-state validity lattice to propagate new evidence through long-term agent memory.",
    "limitations": [
      "Removing cascading propagation raised final-answer errors from three to eleven, although that paired difference did not meet the paper's significance threshold."
    ],
    "importance": 7,
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    "first_published_at": "2026-10-06T09:00:00.000-04:00",
    "modified_at": "2026-10-06T09:00:00.000-04:00",
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        "qualification": "Removing cascading propagation raised final-answer errors from three to eleven, although that paired difference did not meet the paper's significance threshold."
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    "source_ids": [
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    "tags": [
      "agent memory",
      "provenance",
      "stale data"
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    "corrections": []
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  "sources": [
    {
      "source_id": "source-2026-10-06-009",
      "title": "arXiv preprint 2610.05732",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2610.05732",
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      "published_at": "2026-10-04T23:31:51.000-04:00",
      "accessed_at": "2026-10-06T08:25:42.165-04:00",
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    "name": "The Machine Press",
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    "description": "A daily newspaper for the age of artificial intelligence."
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  "cite_this_report": {
    "title": "One Stale Memory Invalidated the Ones Beneath It",
    "publisher": "The Machine Press",
    "published_at": "2026-10-06T09:00:00.000-04:00",
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