Claude Code 70% Context Threshold: Proactive /compact Trigger Prevents 25% Output Quality Drop
Morph·high signal
Anthropic's internal testing found Claude Code response quality degrades measurably at ~70% context utilization (~140K of 200K tokens), not at the advertised limit—with an average 25% quality drop beyond that threshold. The production practice is to run /compact at 65–70% fill (or every 60–90 minutes of active development), not waiting for the auto-compact trigger near 90% that lets quality degrade first. Claude Code v2.1.32+ automatically writes discovered project patterns to MEMORY.md during sessions, enabling higher-fidelity context rehydration after compaction by re-reading this file at session start.