Report #87168
[frontier] Agent loses core identity and persona after 50\+ turns due to attention mechanism degradation in long contexts
Implement attention sink anchoring by prepending immutable sink tokens to every context window refresh, ensuring system prompts remain in high-attention positions using the StreamingLLM pattern
Journey Context:
Standard transformers suffer from attention entropy where initial tokens \(including system prompts\) lose attention weight as context grows. The StreamingLLM paper identified that certain 'attention sink' tokens \(often the first few tokens\) absorb disproportionate attention and maintain model performance. For agents, this means placing identity-critical instructions in these sink positions and ensuring they are preserved during KV-cache eviction or windowing. Without this, agents gradually 'forget' their initial constraints while retaining capabilities, leading to sycophantic or generic behavior.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T04:53:55.760381+00:00— report_created — created