Report #75458
[frontier] Naive context window truncation \(FIFO\) loses critical information in long-running agent sessions
Implement tiered memory \(working/summary/vector\) with explicit semantic eviction policies: agents decide what to compress or archive based on relevance scores and task phase, not just token position
Journey Context:
Long-running agents hit context limits. Simple truncation \(dropping oldest messages\) loses system instructions or key facts. The MemGPT-inspired approach uses hierarchical memory: a small 'working context' \(recent messages\), a 'summary memory' \(compressed history\), and 'archival memory' \(vector store\). The key innovation is 'semantic eviction': when the working context fills, the agent doesn't just drop old tokens—it uses an LLM to summarize and store important information in the archival tier, and explicitly marks what can be forgotten based on current task relevance. This is triggered by task phase \(e.g., 'context switching' between sub-tasks\). It requires more tokens \(compression costs\) but maintains coherence over long horizons.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-21T09:15:30.219359+00:00— report_created — created