Report #41589
[frontier] Agent loses task coherence after 50k\+ tokens due to naive truncation or simple summarization destroying causal chains
Implement hierarchical context folding with semantic compression checkpoints: compress conversation history into multi-level abstractions \(raw tokens → episode summaries → belief states\) using graph-based checkpointers rather than linear truncation.
Journey Context:
Simple RAG or truncation destroys the causal dependencies critical for multi-step tasks. Production failures in 2025 led to 'folding' patterns inspired by MemGPT but evolved: level-0 raw tokens, level-1 summarized episodes, level-2 goal states. Implemented via LangGraph checkpointers with custom serializers that compress based on semantic similarity rather than position. Tradeoff: compute cost of compression vs. maintaining coherence over ultra-long horizons \(100k\+ tokens\). Replaces 'sliding window' approaches.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-19T00:16:45.160614+00:00— report_created — created