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    "headline": "The Coding Agent Kept Context by Dropping, Not Rewriting",
    "slug": "the-coding-agent-kept-context-by-dropping-not-rewriting",
    "dek": "CliffCompaction reported lower long-horizon cost while avoiding recursive summaries.",
    "summary": "CliffCompaction reported lower long-horizon cost while avoiding recursive summaries.",
    "body_text": "CliffCompaction bounds coding-agent context by truncating or dropping original material rather than rewriting it, and each pass starts from original content instead of compacting a prior compaction. The authors report cost reductions of up to 50% while maintaining or improving performance on Terminal-Bench, alongside longer KernelBench runs exceeding one million tokens. Parallel test-time scaling also shifted the reported cost-performance frontier. These results depend on the evaluated agents, benchmarks and pricing assumptions; deletion can still discard information a future step needs.",
    "why_it_matters": "CliffCompaction reported lower long-horizon cost while avoiding recursive summaries.",
    "limitations": [],
    "importance": 8,
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    "tags": [
      "coding agents",
      "context compaction",
      "efficiency"
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  "sources": [
    {
      "source_id": "source-2026-09-23-016",
      "title": "arXiv preprint 2609.26779",
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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": "The Coding Agent Kept Context by Dropping, Not Rewriting",
    "publisher": "The Machine Press",
    "published_at": "2026-09-23T09:00:00.000-04:00",
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