fix(session): prevent context overflow by adding safety margin to compaction check#6562
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o1x3 wants to merge 2 commits intoanomalyco:devfrom
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fix(session): prevent context overflow by adding safety margin to compaction check#6562o1x3 wants to merge 2 commits intoanomalyco:devfrom
o1x3 wants to merge 2 commits intoanomalyco:devfrom
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…paction check - Add 50K overhead buffer to account for system prompts and tool definitions - Add mid-turn overflow detection in finish-step to catch runaway tool loops - Add 30K truncation for MCP tool outputs and webfetch results - Handle compact signal to trigger compaction mid-turn Fixes anomalyco#6068
This was referenced Jan 20, 2026
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Summary
Fixes #6068 - Auto compaction not triggering reliably with Anthropic models causing "prompt is too long" errors.
Root cause: The overflow check happens before system prompts (~25K tokens) and tool definitions (~10K tokens) are added to the request, so 40-60K tokens of overhead aren't accounted for.
Changes:
isOverflow()calculationfinish-stephandlerTest plan