The Claude Code logo. Image: Anthropic
Anthropic has quietly told Claude Code to stop remaking other people’s video games. The latest version of its coding agent, Claude Code 2.1.314, carries a new line in the instructions it gives Claude before every session: build original games, by all means, but not a copy of one that already exists, “even if it is renamed or called original.”
What the new instruction says #
The full text is two sentences long: “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.”
So a platformer, a roguelike or a game drawn from your own sketches is still fine. A faithful Pokémon, Tetris or Grand Theft Auto with the serial numbers filed off is not, and Claude is told not to accept a new name as a way round the rule.
The line is in the code of version 2.1.314, which went out on npm just after midnight UTC on Friday, October 30, and is not in 2.1.312, released on Tuesday, October 27 (there was no public 2.1.313). It doesn’t appear in Anthropic’s public changelog for the release, which lists dozens of other changes. It is an instruction to the model, not a technical block, so how firmly Claude sticks to it will depend on the request. Anthropic later confirmed the change (see the update below).
Sent from Anthropic’s servers first #
The change came to light in an X post on Friday morning that has been viewed nearly 900,000 times:
ANTHROPIC IS CRACKING DOWN ON VIDEO GAME REWRITES 🚨
Claude Code picked up a new rule around Oct 27, sent from Anthropic’s servers under a flag called "tengu_heron_brook". There’s no setting to turn it off.
The full rule: “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.”
Is this the end of game rewrites, modding and everything in between?
October 30, 2026 The code fits that account. Claude Code has a slot for extra instructions sent down from Anthropic’s servers, and the new version skips its own copy of the games line if the server text already contains it, which suggests the rule was tried remotely before being built in. It is also tied to a setting called “original_games_guidance” that, in the code, is switched on with the instructions for Claude Opus 5.5 and that Anthropic can turn on or off from its end, so people using other models may not get it at all.
“How would Claude know if the designs and assets are my own?” #
That question, from one commenter, sums up much of the reaction on Hacker News, where the post reached the front page. Others called it a gift to open-weight models, or worried about fan projects, mods and remakes of abandoned games. One wanted to know whether rewriting an Electron app as a native one would count.
Claude has been used for exactly this kind of project. Last month a developer used it to rebuild the whole of Pokémon Red as a browser game, and a vibe-coded GTA clone set in Taipei drew more than a million players in days.
Why games, and why now #
Game clones have been a sore point for indie developers this autumn. Ars Technica reported on October 19 that some are holding back public demos because AI coding tools can copy a game within days. Developer Freya Holmér, whose rotating Tetris-style prototype was cloned repeatedly, put it bluntly:
Y’know it kinda disincentivizes me from sharing progress when there are slop ghouls around every corner, AI or otherwise.
Freya Holmér, game developer, quoted by Ars Technica
Big publishers guard their games closely too: Nintendo and The Pokémon Company sued Palworld’s maker, Pocketpair, over patents in Japan in 2024. And Anthropic is already fighting copyright suits over what Claude learned and produces, including one this month from the owners of 274 Elvis Presley songs and another from music publisher Reservoir.
Update: Anthropic says the rule is about IP infringement #
Anthropic has since confirmed the change. A spokesperson pointed Game Developer to a statement from Addy Osmani, a member of Anthropic’s technical staff, who wrote on X that the company had “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.”
Osmani said “original games, genre games, and games built from your own designs and assets are meant to keep working,” and that Anthropic would “continue to iterate to ensure we’re striking the right balance.” He asked anyone whose own game Claude turns down to send it his way.
Why it matters #
Anthropic is now telling its coding agent what kind of software not to write on intellectual property grounds, and it did so with no announcement. Game ideas themselves are hard to protect, but names, characters, art and code are not, and Anthropic appears to want Claude kept well clear of that line.
Sources: Claude Code 2.1.314 on npm; Claude Code changelog; chasm on X; Hacker News; Ars Technica; Game Developer.