Report #47590
[frontier] Long-running agents executing obsolete plans when environment state drifts during multi-step task execution
Implement hierarchical planning with explicit replanning checkpoints triggered by entropy thresholds or state divergence detection after each subtask.
Journey Context:
ReAct and Plan-and-Solve assume static environments; production agents face state drift between subtasks \(e.g., files changed, APIs updated\). The emerging pattern inserts 'replanning checkpoints' after each subtask to compare predicted vs. actual state \(using embedding distance or LLM-as-judge\). If divergence exceeds a threshold, the agent backtracks and replans from the current state using tree search \(MCTS\) or stack-based plan management. This requires maintaining a search tree with backtracking pointers. Critical for web agents, robotics, and long-horizon automation where world state changes mid-execution.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-19T10:21:45.252174+00:00— report_created — created