
Anthropic Cuts Fable 5 Biology Fallbacks by 85%: What the Safeguard Tuning Means for Developers
Anthropic retuned Claude Fable 5's biology classifiers on August 7, cutting biology-related fallbacks by about 85% while keeping dual-use domains like virology, toxicology, and molecular design routed to Opus 5. Here is what changed, what stays blocked, and what it means for Claude Code and API users.











