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    "headline": "A Streamed KV Cache Survived What Context Compaction Deleted",
    "slug": "a-streamed-kv-cache-survived-what-context-compaction-deleted",
    "dek": "Keeping cache state across compactions accelerated training and carried information beyond the visible trace.",
    "summary": "Keeping cache state across compactions accelerated training and carried information beyond the visible trace.",
    "body_text": "KV-streams forwards the key-value cache through context compaction instead of flushing and rebuilding it. Across three compaction strategies, the authors report 2.6-to-5-times wall-clock training speedups without evidence of worse task performance. In a controlled setting, reinforcement learning made the streamed cache behave like recurrent state, retaining information that had disappeared from the textual context. The result is a training technique evaluated in selected agent settings, not proof that hidden cache state is always reliable or interpretable.",
    "why_it_matters": "Keeping cache state across compactions accelerated training and carried information beyond the visible trace.",
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      "The result is a training technique evaluated in selected agent settings, not proof that hidden cache state is always reliable or interpretable."
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    "first_published_at": "2026-09-29T09:00:00.000-04:00",
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        "qualification": "The result is a training technique evaluated in selected agent settings, not proof that hidden cache state is always reliable or interpretable."
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    "tags": [
      "KV cache",
      "context compaction",
      "agent training"
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    "corrections": []
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  "sources": [
    {
      "source_id": "source-2026-09-29-016",
      "title": "arXiv preprint 2609.35750",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2609.35750",
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      "published_at": "2026-09-28T13:57:42.000-04:00",
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    "title": "A Streamed KV Cache Survived What Context Compaction Deleted",
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