Add `coreMemory.refreshAtContextPercent` config option to re-inject
core memories when context usage exceeds a threshold. This counters
the "lost in the middle" phenomenon documented by Liu et al. (2023).
Implementation:
- Extend before_agent_start hook event with context usage info
- Pass contextWindowTokens and estimatedUsedTokens to hooks
- Track mid-session refresh per session to prevent over-refreshing
- Clear refresh tracking on compaction
- Add comprehensive tests
Based on research: Liu et al., "Lost in the Middle: How Language
Models Use Long Contexts" (Stanford, 2023)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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