Anthropic has updated the system prompt for Claude Code to stop the tool being used to recreate existing video games, while keeping it available for making original ones. Addy Osmani of Anthropic, replying to a post on X, said the company added two sentences to the Claude Code prompt on Opus 5.5 to steer it away from recreating someone else's specific game, because using Claude to infringe IP is against its usage policy. He said original games, games in a genre, and games built from a user's own designs and assets are meant to keep working, and that the company would keep iterating to strike the right balance, inviting anyone whose own work is turned down to send it to him.
The Verge reports that retro gaming is currently being overrun with AI-made decompilations, recompilations and ports. Anthropic will still let people use Claude Code to make games, but it does not want people to use it for direct clones of specific titles.
The screenshot that first drew attention to the update was posted on X by a user last week, and allegedly showed two sentences added to the Claude Code system prompt: "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 named or called original." Osmani did not confirm that specific language in his reply, according to The Verge's account, but said the prompt had been updated on Opus 5.5.
The Verge has asked Anthropic whether it has or will be updating other Claude system prompts as well.
Analysis
Why This Matters
- Anthropic is drawing a line between using Claude Code as a game-building tool and using it to reproduce games someone else made, a distinction likely to be tested by other AI coding assistants.
- Developers who use Claude Code for fan projects, ports or decompilations may find requests refused, while original and genre work is meant to continue.
- How Anthropic words and enforces the rule will shape what rights holders can point to when AI tools are used to reproduce their titles.
Background
Anthropic is an AI company and Claude Code is its coding tool, which runs on its Claude models. As AI coding assistants have become more capable, companies that make them have faced questions about how their output is used, including whether generated code reproduces material owned by others. Anthropic's stated usage policy against IP infringement is the basis it gives for the prompt change. The update applies to Claude Code on Opus 5.5.
What to Watch
- Whether Anthropic extends the restriction to other Claude system prompts, which The Verge has asked about.
- Whether the wording of the system prompt circulates and is compared with the two sentences shown in the screenshot, which Anthropic has not confirmed.
- How users report the rule working in practice, given Osmani's invitation to flag cases where Claude refuses work that belongs to the user.
Checked
12 claims in this story checked against 1 source: 10 supported.
Show each claim
- SupportedAnthropic is steering Claude Code away from recreating existing video games.The Verge: “Anthropic has updated Claude Code’s system prompt to prevent the AI tool from being used to recreate existing video games”
- SupportedAnthropic says using Claude to infringe intellectual property violates its usage policy.The Verge: “because using Claude to infringe IP is against our usage policy.”
- SupportedOriginal games and games made from a user’s own designs and assets are meant to keep working.The Verge: “Original games, genre games, and games built from your own designs and assets are meant to keep working.”
- SupportedAnthropic added two sentences to the Claude Code prompt on Opus 5.5 to steer it away from recreating someone else’s specific game.The Verge: “We added two sentences to Claude Code’s prompt on Opus 5.5 to steer it away from recreating someone else’s specific game”
- Reports differThe screenshot’s alleged prompt text says, “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 named or called original.”The Verge: ““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 named or called original.””
- SupportedOsmani said the prompt change was intended to steer Claude away from recreating someone else’s specific game because using Claude to infringe IP violates the policy.The Verge: “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.”
- SupportedOsmani said original games, games in a genre, and games built from users’ own designs and assets are meant to keep working.The Verge: “Original games, genre games, and games built from your own designs and assets are meant to keep working.”
- SupportedOsmani said Anthropic would keep iterating to strike the right balance.The Verge: “We’ll continue to iterate to ensure we’re striking the right balance.”
- SupportedThe Verge reports that retro gaming is currently being overrun with AI-made decompilations, recompilations and ports.The Verge: “Retro gaming is currently being overrun with AI-made decompilations, recompilations, and ports”
- SupportedAnthropic will still let people use Claude Code to make games, but does not want direct clones of specific titles.The Verge: “Anthropic will still let people use Claude Code to make games, it doesn’t want people to use it for direct clones.”
- Partly supportedThe screenshot that first drew attention to the update was posted on X by a user last week.The Verge: “Last week, a user on X posted a screenshot allegedly showing two new sentences added to Claude Code’s system prompt”
- SupportedOsmani did not confirm the screenshot’s specific wording, but said the prompt had been updated on Opus 5.5.The Verge: “Anthropic’s Addy Osmani, in a reply, didn’t confirm that specific language but did say that the company had updated the prompt in Claude Code on Opus 5.5”