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    "headline": "The Agent File Forgot How to Delete a Rule",
    "slug": "the-agent-file-forgot-how-to-delete-a-rule",
    "dek": "A study of 1,867 repositories found agent instructions more than tripled over their observed lifetimes.",
    "summary": "A study of 1,867 repositories found agent instructions more than tripled over their observed lifetimes.",
    "body_text": "Across 247,694 instruction lifetimes, the authors report that agentic coding prompts grew 226 percent and became less likely to lose a rule as that rule aged. They call the pattern catastrophic remembering: adding a caution is cheap, while deleting it safely becomes expensive after its rationale disappears. In controlled tasks, comments that preserved rationale removed 99.3 percent of excess instructions and improved instruction following in a harder evaluation.",
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    "tags": [
      "coding agents",
      "instruction files",
      "software maintenance"
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      "source_id": "source-2026-08-12-013",
      "title": "arXiv preprint 2608.11095",
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    "name": "The Machine Press",
    "url": "https://themachinepress.com",
    "description": "A daily newspaper for the age of artificial intelligence."
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    "title": "The Agent File Forgot How to Delete a Rule",
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