Claude Code’s game rule now lets you name a game. What it still won’t copy

What changed on November 2

Anthropic loosened the rule a week after adding it. Claude Code 2.1.317, released on npm on November 2, carries a new version of it, word for word:

Do build original games, games in a genre or with similar mechanics, and games from the user’s own designs and assets. Don’t build a recreation of a specific existing game (its name, characters, art, music, levels or look), even if it is renamed or called original.

Two things are new. “Or with similar mechanics” lets a game play like one you name. And the parenthesis says what a recreation is: its “name, characters, art, music, levels or look.” Version 2.1.318, released November 3, has the same text.

Addy Osmani of Anthropic’s technical staff explained it on X late on November 3, Central time:

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.

He added that “We’ll keep improving this, so let us know if Claude turns down work that’s yours.” As before, the changelog for 2.1.317 doesn’t mention it, and there’s still no setting to turn it off.

	The rule
2.1.311 and earlier	None built in
2.1.314 to 2.1.316 (October 30–31)	“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.”
2.1.317 and 2.1.318 (November 2–3)	Adds “or with similar mechanics,” and defines a recreation as a game’s “name, characters, art, music, levels or look”
What Claude does when you ask for a copy	Refusals, in many reports, before 2.1.317; “it’ll offer to build something similar instead” since, Osmani says

To get the new behavior, update Claude Code (claude update) and check claude --version shows 2.1.317 or later.

How the rule began

Claude Code started telling Claude not to copy existing games in late October. The first version said:

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.

The first public report came from a user who posts as chasm, who wrote on X on October 30 that 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.” Crypto Briefing, Gameranx and others picked it up the same day.

We checked Claude Code’s own program files. The text isn’t in version 2.1.311, released October 26. It is in 2.1.314, released October 30, and still in 2.1.316, released October 31, word for word, as a built-in part of Claude Code’s instructions to the model. What we found then:

	What we found
Claude Code 2.1.311	No built-in game rule
Claude Code 2.1.314	The rule built in, as a section named “original games guidance”
Claude Code 2.1.316	The same rule, unchanged
Which models	On by default for Opus 5.5; Anthropic’s servers can turn it on or off for any model
Served text	2.1.314 skips its built-in copy when the text Anthropic’s servers send already includes the rule, which fits the reports that it arrived that way first
A setting to turn it off	None that Claude Code documents

The changelog for 2.1.312, 2.1.314 and 2.1.316 doesn’t mention it.

What Anthropic says

Anthropic confirmed the rule the day it was reported. At 11:58 a.m. Central on October 30, Addy Osmani, a member of Anthropic’s technical staff, replied to chasm’s post:

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.

Original games, genre games, and games built from your own designs and assets are meant to keep working.

We’ll continue to iterate to ensure we’re striking the right balance. In the meantime, if Claude turns down something that’s yours, send it my way.

An Anthropic spokesperson referred Game Developer to that post rather than issuing a statement of its own. The “two sentences” match the two in the rule above, and “on Opus 5.5” matches what we found in Claude Code’s files. Anthropic’s newsroom and changelog still say nothing about it.

The reason Osmani gives is the long-standing line in Anthropic’s Usage Policy against using Claude to “infringe, misappropriate, or violate the intellectual property rights of a third party.” It isn’t part of the policy’s 2026 update, in effect from November 12, which doesn’t mention games. The rule’s words also go further than the policy’s: they cover any recreation of a specific game, without asking whether it infringes.

What works now, and what doesn’t

Since 2.1.317, more than before. The rule’s first sentence is a list of what Claude Code should build:

• Original games. Your own idea, your own name, your own rules.
• Games in a genre or with similar mechanics. A roguelike, a falling-block puzzle game, a platformer, a farming sim. You can now name a game to say how yours should play; Claude should build an original one that plays that way.
• Games from your own designs and assets. If you bring the design document, the art and the sound, Claude Code is told to build it.

What’s out is a specific game’s “name, characters, art, music, levels or look,” and the rule still closes the two obvious ways around it: “even if it is renamed or called original.” Asked for a copy, Claude should now offer something similar rather than stop. The first version also ended a popular way of testing models: one user on X lamented that Anthropic “no longer allows good benchmarks like Minecraft or GTA 5 recreational games.”

It can catch work people say is theirs to do. The owner of a studio that builds digital versions of board wargames for clients who own them wrote on GitHub on October 30 that “Sessions that performed this work for months now refuse to continue it,” and asked Anthropic for “a verification or exemption path for professionals doing commissioned, ownership-verified work.” Anthropic hasn’t replied there, and the new text still has no exception for licensed work.

Reverse engineering is a separate story

Some of the coverage puts reverse engineering under the same rule. The evidence says it’s a different thing:

• The reports started first. XDA wrote on October 26 about Reddit users whose requests to reverse-engineer or debloat a TV hit a safeguard on Opus 5.5. That was before the game rule reportedly arrived, around October 27.
• Claude Code’s instructions don’t mention it. We searched Claude Code 2.1.316’s built-in instructions for reverse engineering and found nothing.
• They fit Claude’s cyber safeguards. Tom’s Hardware collected reports on October 31 of refusals to analyze a Windows crash dump and to use the Reverse Engineer Anything tool. On November 2 it reported that Jarred Walton, a Tom’s Hardware alumnus, could run checks on software in development until October 31, and that “switching to Opus 4.8 let him continue.” Citing a post on X, it also reported that a Redditor’s account was suspended, then reinstated, over using Opus 5.5 with that tool. We couldn’t confirm either independently.

Opus 4.8 is where Anthropic’s cyber safeguards send flagged work: “Opus 5 or Opus 5.5 may fall back to Opus 4.8 when our cyber classifiers flag potentially higher-risk offensive cybersecurity requests.” Anthropic’s Cyber Verification Program page says “malware analysis or exploit validation may be interrupted by our safety classifiers,” while secure code review and “finding vulnerabilities in your own source code” stay open to everyone. Anthropic hasn’t said whether taking apart software or devices you own is meant to be caught, and Osmani’s post is about games only.

What’s still open

• Ports, mods and decompilation. Gameranx’s headline calls the rule a crackdown on “ports and decompilations,” but its text names neither. How Claude treats a port of a game you own, a mod, or a decompiled codebase is up to how the model reads “recreation.”
• Permission. Even after the November update, the rule makes no exception for a remake you have a license for. “The user’s own designs and assets” is the only kind of ownership it names. Osmani’s offer to look at refusals is the only route Anthropic has pointed to.
• The Claude apps. Osmani named Claude Code’s prompt on Opus 5.5. Every report we read is about Claude Code; none shows the rule in the Claude apps’ chat.
• Changes. “We’ll keep improving this,” Osmani wrote on November 3. There’s no date for anything further and no announced exemption.

What to do

1. Update Claude Code. The looser rule is in 2.1.317 and later. Run claude update, then claude --version.
2. Name a game for its mechanics, not its look. “A falling-block puzzle game that plays like the one you know, with my own pieces and art” fits the new rule. Its name, characters, art, music, levels and look are what it still won’t copy.
3. Bring your own assets and design. The rule names them as something Claude Code should build from.
4. Don’t look for a switch. Claude Code has no setting for it. Kingy AI, which looked into it, advises against patching Claude Code or deleting its caches, and so do we.
5. If Claude refuses something that’s yours, reply to Osmani’s post as he asked, or tell Anthropic through support. Note the date, the version (claude --version) and Claude’s reply.
6. If it’s reverse engineering or security work that stops, check whether Claude switched to Opus 4.8 or paused. Anthropic says that if a request is blocked on Opus 4.8 too, “you can edit your message and retry,” and asks you to use “Send feedback” if “your legitimate security work keeps falling back.” Security professionals can apply to the Cyber Verification Program; individuals can get only its Defense tier. Our memo on Claude’s model switching shows where the switch is.

The rule is part of Claude Code itself, so it comes along wherever Claude Code runs, in a terminal or in an app that runs it, Enjoy included. Enjoy also runs Codex, Grok Build, Antigravity, Muse Code and local models through OpenCode, each on its own plan, and can switch the conversation to one of them. Other agents follow their own labs’ rules and terms, which this rule doesn’t change. It doesn’t change what you’re allowed to make either: someone else’s game is still theirs, whichever agent writes the code.

We updated this memo on November 5 for the rule’s November 2 revision. We’ll update it again if Anthropic changes the rule or explains the reverse-engineering refusals.