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    "story_id": "mp-2026-09-18-003",
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    "headline": "Context Management Mostly Bought Agents More Time",
    "slug": "context-management-mostly-bought-agents-more-time",
    "dek": "Across 176 matched settings, overflow prevention—not recoverable elision—delivered most of the context-management gain.",
    "summary": "Across 176 matched settings, overflow prevention—not recoverable elision—delivered most of the context-management gain.",
    "body_text": "A fixed execution loop let researchers vary planning, action space and context management separately across four models on SWE-Bench Verified and Terminal-Bench 2.1. Rule-based elision followed by model summarization produced the strongest overall efficiency, while machinery for recovering elided content saw little use and no accuracy gain. Planning shifted from an accuracy scaffold for weaker models to a cost saver for stronger ones. Predefined tools helped models with weaker shell skills; bash-capable models worked more cheaply with bash alone. The 176-setting study argues that harness value depends on model and budget, not one universal stack.",
    "why_it_matters": "Across 176 matched settings, overflow prevention—not recoverable elision—delivered most of the context-management gain.",
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      "The 176-setting study argues that harness value depends on model and budget, not one universal stack."
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        "text": "Across 176 matched settings, overflow prevention—not recoverable elision—delivered most of the context-management gain.",
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    "tags": [
      "coding agents",
      "context management",
      "software engineering"
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      "source_id": "source-2026-09-18-003",
      "title": "arXiv preprint 2609.20804",
      "publisher": "arXiv",
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      "published_at": "2026-09-17T13:58:07.000-04:00",
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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": "Context Management Mostly Bought Agents More Time",
    "publisher": "The Machine Press",
    "published_at": "2026-09-18T09:00:00.000-04:00",
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