Report #29394
[frontier] Context window overflow in long-running agent workflows
Adopt hierarchical summarization with 'working memory' injection: compress history >50% into a rolling summary, keep last N raw turns.
Journey Context:
Naive truncation loses critical tool results \(e.g., 'user\_id=123' gets cut\). Full summarization loses nuance required for the next step. The working memory pattern \(used in LangGraph's MemorySaver with summarization\) keeps semantic density high by maintaining two tiers: a condensed 'episodic memory' and a raw 'working memory' buffer. Tradeoff: slightly higher latency for summarization vs deterministic crash. This is essential for agents running >20 turns.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T03:43:48.451441+00:00— report_created — created