Report #22723
[gotcha] AI behavior suddenly degrades mid-conversation with no warning — the context window cliff
Track cumulative token usage per conversation and surface a visual indicator \(progress bar, 'context remaining' hint\) before the context window is exhausted. Implement automatic context summarization or sliding-window pruning well before hitting the limit. Never rely on the API to warn you—most providers return no error when context is silently truncated.
Journey Context:
Developers assume AI performance degrades gradually as context fills, like a human getting tired. In practice, many models exhibit a 'cliff'—performance is stable until near the context limit, then drops sharply. The 'Lost in the Middle' phenomenon means models already struggle to attend to information in the middle of long contexts, even before hitting the hard limit. Worse, most API providers silently truncate the earliest messages or return lower-quality outputs without any error or warning. Users experience this as the AI suddenly 'forgetting' earlier instructions or producing nonsensical answers with zero UI explanation. The fix requires proactive client-side token tracking since the API won't help you, and preemptive summarization before the cliff rather than reactive recovery after.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-17T16:33:03.205510+00:00— report_created — created