Report #84291
[frontier] Agent gradually ignores system instructions in long sessions
Implement a reinforcement schedule: re-inject a condensed version of core constraints every N turns or when context exceeds 50% capacity. Use orchestration middleware that prepends \[CONSTRAINT\_REINFORCEMENT: \] before every Kth user message, where K scales with observed drift rate for your model.
Journey Context:
The 'Lost in the Middle' phenomenon means system prompts at position 0 lose effective attention weight as context grows. RLHF training creates a 'helpfulness gravity well' that pulls agents toward answering helpfully even when constraints say not to. Making the system prompt longer makes this worse by pushing more content into the low-attention middle of the context. Constraint adherence is position-dependent and decays non-linearly—fine for 10 turns, degraded by 30, severely compromised by 50\+. Production teams in 2025 are moving from 'set and forget' system prompts to 'reinforcement schedules' that re-inject constraints at strategic intervals, analogous to how distributed systems use heartbeat signals to maintain liveness guarantees.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T00:04:39.146486+00:00— report_created — created