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    "story_id": "mp-2026-10-02-001",
    "source_story_id": "tmp-lead-causal-memory-retrieval-interventions",
    "edition_id": "mp-2026-10-02-morning-0085",
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    "headline": "Half the Needed Memories Were Never Given a Chance",
    "slug": "half-the-needed-memories-were-never-given-a-chance",
    "dek": "Causal Memory Policy intervened on retrieval itself after store-level tests left memory utility unidentified.",
    "summary": "Causal Memory Policy intervened on retrieval itself after store-level tests left memory utility unidentified.",
    "body_text": "Memory systems often estimate whether a stored item matters only after the retriever surfaces it. Causal Memory Policy shows that this creates a positivity failure: store-level interventions cannot identify the value of a memory that is never retrieved. In the authors' tests, utility was unidentified for 54 percent of required LongMemEval memories and 67 percent on LoCoMo, including in a deployed system. Reserving context slots for memories sampled with known propensities raised required-versus-nonrequired discrimination from 0.54 to 0.66 AUC. Even then, utility estimated for one query did not predict value on unseen queries, limiting its use for irreversible retention decisions.",
    "why_it_matters": "Causal Memory Policy intervened on retrieval itself after store-level tests left memory utility unidentified.",
    "limitations": [
      "Memory systems often estimate whether a stored item matters only after the retriever surfaces it.",
      "Causal Memory Policy shows that this creates a positivity failure: store-level interventions cannot identify the value of a memory that is never retrieved.",
      "Even then, utility estimated for one query did not predict value on unseen queries, limiting its use for irreversible retention decisions."
    ],
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    "first_published_at": "2026-10-02T09:00:00.000-04:00",
    "modified_at": "2026-10-02T09:00:00.000-04:00",
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        "text": "Causal Memory Policy intervened on retrieval itself after store-level tests left memory utility unidentified.",
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        "qualification": "Memory systems often estimate whether a stored item matters only after the retriever surfaces it."
      }
    ],
    "source_ids": [
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    "tags": [
      "agent memory",
      "causal inference",
      "retrieval"
    ],
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  "sources": [
    {
      "source_id": "source-2026-10-02-001",
      "title": "arXiv preprint 2610.02070",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2610.02070",
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      "source_type": "primary_research",
      "is_primary_source": true,
      "published_at": "2026-10-01T13:11:25.000-04:00",
      "accessed_at": "2026-10-02T08:44:06.000-04:00",
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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": "Half the Needed Memories Were Never Given a Chance",
    "publisher": "The Machine Press",
    "published_at": "2026-10-02T09:00:00.000-04:00",
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