Anthropic says Claude Opus 5.5 is the first model in its Claude 5.5 family and performs at the level of Claude Fable 5.1 on most work while costing 40% less than Opus 5. The company reports gains in coding, knowledge work, and computer-use evaluations, with results tied to its stated test settings. Higher-risk biology and cybersecurity uses remain subject to safeguards and verification programs.

Editor's note

This summary is based on the primary source. Open the original for full context, data, and qualifying details.