Improving Fable 5's biology safeguards

We’re making updates to Claude Fable 5’s biology safeguards in a way that substantially reduces false positives. Fable 5 users will now experience many fewer “fallbacks”—where the system switches to a less capable model after they make a biology-related query. In our testing, this update reduced biology-related fallbacks by about 85% across our product surfaces. 1 Fable 5 will thus be able to assist with a wider range of biology tasks. In practice, users should see far fewer fallbacks on everyda