Claude urgently halted! Secretly modified Harness to prohibit reverse-engineering games

What happened: Anthropic confirmed it added two lines to the Opus 5.5 system prompt telling Claude not to recreate a specific game that belongs to someone else, after a user flagged that Claude Code appeared to block game cloning. Key numbers: Opus 5.5 released September 22. Why it matters: The article argues the rule only binds Claude, so cloning can move to other models or be split into narrow tasks, while GitHub issues show original projects wrongly refused. It calls this the game industry's Napster moment.

Anthropic confirmed it added two lines to the Opus 5.5 system prompt telling Claude not to recreate a specific game that belongs to someone else, after a user flagged that Claude Code appeared to block game cloning.

The article argues the rule only binds Claude, so cloning can move to other models or be split into narrow tasks, while GitHub issues show original projects wrongly refused. It calls this the game industry's Napster moment.