Two sentences. No more remakes.

What happened

Around October 27, 2026, Claude Code, Anthropic’s coding agent, started receiving a new instruction from Anthropic’s servers. The user who spotted it, chasm on X, posted it on October 30: “Do build original games, games in a genre, and games from the user’s own designs and assets. Don’t build a recreation of a specific existing game, even if it is renamed or called original.” He said it arrived under a configuration flag called “tengu_heron_brook” and that there is no setting to turn it off. By the next day the post had about 1.9 million views.

XDA Developers says it found the exact text inside version 2.1.314 of the Claude Code program, along with a separate mechanism that can apply it to Opus 5.5 on its own. MadRobot reports that the text is not in 2.1.312, released October 27, and that the public changelog for the new version doesn’t mention it. Version 2.1.314 went out on npm on October 30, just after midnight UTC.

Anthropic confirmed the change the same day. “We added two sentences to Claude Code’s prompt on Opus 5.5 to steer it away from recreating someone else’s specific game because using Claude to infringe IP is against our usage policy,” Addy Osmani, a member of Anthropic’s technical staff, wrote on X. “Original games, genre games, and games built from your own designs and assets are meant to keep working.” He asked anyone whose own game Claude turns down to send it to him. An Anthropic spokesperson pointed Game Developer to that statement.

Hours before the confirmation, a developer who builds digital board-wargame modules for paying clients filed a GitHub report saying Claude Code now refuses work it had done for months. In a follow-up comment he added the strangest detail: the work “ran fine under the new rule until I asked about the rule.” The refusals, he says, began only after he asked Claude to check whether the rule affected his projects, and they continued in new sessions on the same repositories. XDA saw the effect of asking from the other side: when it asked an older model, Opus 5, whether a system instruction was behind a refusal, the model denied having one and offered to help after all.

The limits matter. Anthropic says original, genre and own-asset games should still work, and XDA’s own tests found Opus 5.5 willing to help with a decompilation project. The developer’s timeline is his own account; XDA did not reproduce his refusals, and he corrected his report to say the work is built from materials his clients supply for games they own, not under publisher licenses. Reports of other refusals, including reverse-engineering tasks, are user claims, and Tom’s Hardware notes their link to this rule is unconfirmed. We found no Anthropic reply on the GitHub report as of October 31. This is a policy change working roughly as written, not a breach or an accident.