Livenerf: Has Opus 5.5 been nerfed yet?

LiveNerf is a new public repository launched to monitor the precision of Claude Opus 5.5, which debuted on September 22, 2026. The project aims to detect AI model degradation by comparing current performance against a launch baseline, replacing anecdotal social media complaints with empirical data. Findings indicate that reducing reasoning effort can cut output tokens by up to 62% before performance scores decline. LiveNerf provides a calibrated panel to track these changes daily.