Even requests that merely named a game were refused

Addy Osmani, who works on Claude Code at Anthropic, said on X on Nov. 3 (Nov. 4 Japan time) that a rule refusing to recreate specific existing games had been fixed. He explained that the rule added in late October had also been kicking in for requests that merely named a game to describe the mechanics wanted. It was updated in Claude Code 2.1.317, and he said that if users name a game to describe what they want, Claude Code should build an original game in that genre.

An update on building games with Claude Code: Last week some of you ran into Claude Code pushing back on game projects it should have just built. We'd added a short rule to the Opus 5.5 prompt to steer Claude away from recreating specific existing games, but it was also kicking in when you referenced one just to describe the mechanics you wanted. We've updated that rule in 2.1.317. You can name a game to describe what you want and Claude should now build an original game in that genre. If you ask for a copy of the original, it'll offer to build something similar instead. We want Claude to be as helpful as possible when you're building something original, but also to protect your work if someone else tries to copy it. We'll keep improving this, so let us know if Claude turns down work that's yours. Thanks to everyone who shared feedback!

@addyosmani · November 4, 2026

Claude Code is Anthropic's AI coding tool that writes programs on instruction. The rule is part of the prompt used when Claude Code runs on the company's flagship model, "Claude Opus 5.5." On Oct. 30 (Oct. 31 Japan time), Osmani had explained that two sentences were added to this prompt.

Copy requests not refused, something similar offered

According to Osmani, when asked for a copy of the original game, Claude Code offers to build something similar instead. The prompt added in late October had said it would not build recreations of specific existing games, even if renamed or described as original.

Osmani wrote that the company wants Claude to be as helpful as possible when users build original work, while also protecting users' work if someone else tries to copy it. In his Oct. 30 post, he had said that using Claude to infringe intellectual property violates the company's usage policy.

Handling of licensed work not addressed

Osmani's post did not address work to make digital versions of existing games with permission from rights holders, or ports. On Oct. 30, a developer who makes digital versions of board games commissioned by publishers filed a request on GitHub, saying even licensed work was being refused. The request asks for a prompt limited to actual infringement, a way to confirm permission and an entry in the changelog. As of Nov. 4, the request remained open, with no reply from Anthropic employees.

The changelog entry the request asked for was also absent this time. According to npm's public records, 2.1.317 was released on Nov. 2 (Nov. 3 Japan time), but the 2.1.317 entry in the official changelog has no mention of games or this rule. The text of the revised prompt could not be confirmed as of the evening of Nov. 4.

Osmani said the company will keep improving this and asked users to let it know if their own work is turned down.

Revised a week after it was added

Concern is spreading in the game industry about AI being used to make clones of existing games. According to GameBusiness.jp, cases were reported in October in which indie game developers overseas received threatening emails demanding Steam items or money, saying an AI-made clone would be released first. Indie game developers in Japan also received similar emails, it said.

The rule went in around Oct. 27 and was revised less than a week after users' reports.

Timeline of Claude Code's game recreation rule (dates in U.S. time)
  1. Prompt refusing to recreate existing games added via server-delivered settingsUser report
  2. Users report the prompt's existence on XUser report
  3. Osmani explains two sentences were added to the prompt for Opus 5.5Official
  4. Developer files request on GitHub saying licensed work is refusedUser report
  5. Claude Code 2.1.317 releasedOfficial
  6. Osmani says the rule was fixed in 2.1.317Official