From the article > We removed over 80% of Claude Code’s system prompt for models like Claude Opus 5 and Claude Fable 5 with no measurable loss on our coding ev

From the article > We removed over 80% of Claude Code’s system prompt for models like Claude Opus 5 and Claude Fable 5 with no measurable loss on our coding evaluations. And no report of how it impacted earlier models. Was it just BS all along? 80% of the prompt was wasted tokens.