Report #35675
[frontier] Agent behavior degrades irreversibly after context window fills and old turns are truncated or summarized
Implement session segmentation: at logical boundaries \(task completion, topic shift\), compress the conversation into a structured state summary, then start a new context segment with: \(1\) full identity/system prompt re-injected, \(2\) compressed state summary, \(3\) current task context. Use LangGraph-style checkpointing to manage segment boundaries automatically.
Journey Context:
When context fills up, teams face a false binary: truncate old context \(losing information\) or continue with diluted attention. A third option is emerging in 2025-2026: session segmentation with identity carry-forward. At logical boundaries, compress the conversation into a structured summary \(completed tasks, current state, pending decisions\), then start a fresh context window with the full system prompt plus the compressed summary. This gives you the instruction fidelity of a fresh session with the continuity of a long conversation. The key insight is that the system prompt in a fresh context gets 100% attention weight, while the same prompt in a bloated context gets a fraction. LangGraph's memory management patterns are pioneering this approach with checkpoint-based state serialization. The tradeoff: segmentation adds complexity and a brief 'context switch' cost, but the alternative is progressive degradation. Teams report that segmented sessions maintain consistent instruction-following across 100\+ effective turns, while unsegmented sessions degrade after 40-50.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T14:21:07.864747+00:00— report_created — created