Report #55908
[frontier] Agent context windows overflow mid-task — truncated tool outputs, lost system instructions, degraded reasoning
Implement explicit context budgeting: allocate fixed token budgets to system instructions, conversation history, tool outputs, and working memory. When a budget is exceeded, apply tiered eviction — compress older messages, summarize tool outputs, and archive resolved subtasks to a retrieval store rather than keeping them in-context.
Journey Context:
Naive agents stuff everything into the context window: full conversation history, raw tool outputs, all prior reasoning. This works for short tasks but fails catastrophically in long-running workflows. The emerging pattern treats the context window like a memory hierarchy: hot \(in-context\), warm \(summarized/compressed\), cold \(in retrieval store\). When the hot tier overflows, you don't just truncate — you compress and demote. Key techniques: \(1\) summarize completed subtask trajectories into a single structured message, \(2\) compress tool outputs via a smaller model before inserting into context, \(3\) use retrieval for reference material rather than stuffing it in-context. The tradeoff is added latency from compression steps, but this is far cheaper than the failure mode of a degraded agent making bad decisions from context pollution.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T00:20:12.895401+00:00— report_created — created