I believe you meant to cite the Opus 5.5 System Card which states:

> Claude Opus 5.5 scored 66.36% on Terminal-Bench 4.0 with safeguards enabled; requests flagged by the safeguards were answered by a fallback model following the default server-side fallback policy (2.5% of requests, affecting 10% of trials).

> https://www-cdn.anthropic.com/fc1b44717c85dc068bc6ba50242199...

I cannot find a Sonnet 5.5 system card.