Livenerf: Has Claude Opus 5.5 Been Nerfed Yet?
Livenerf is a 30-day benchmark built to test whether Claude Opus 5.5 gets weaker after launch. By freezing the prompts, panel, harness, and graders, it replaces post-release anecdotes with a time series—and, as of September 30, 2026, it is still collecting baseline data.