Artificial Intelligence
Anthropic tightens Claude Code rules on game cloning
Anthropic said Claude Code now blocked attempts to copy existing video games, after users had been using the tool and other AI systems to produce unofficial ports and knockoffs.
- Anthropic had changed two sentences in Claude Code's system prompt for Opus 5.5, according to Addy Osmani.
- Osmani said the change stopped Claude Code from cloning other people's games, including renamed copies passed off as original work.
- He said users could still build their own games and projects with custom assets, although some reported problems with original projects too.
- The article said users had been using Opus 5.5 and GPT-6 Astra to produce unofficial browser ports of well-known titles.
- Osmani said Anthropic planned to keep adjusting the rules going forward.
Anthropic had altered two lines in the system prompt for Claude Code's Opus 5.5 version, Addy Osmani said on X. He said the change was meant to stop the tool being used to clone other people's games.
The restriction had been active for several days and applied even when a copy was renamed or presented as original work. Osmani said people could still make their own games, genre titles and projects with custom assets, although some users reported trouble with original projects as well.
The article said the change came after a rise in AI-assisted cloning projects. It said people had been using Opus 5.5 and GPT-6 Astra to produce many unofficial browser ports of well-known games, while Reverse Engineer Anything was used with reverse engineering to turn binaries into pseudocode.
The piece also said one developer had gained attention for recreating parts of Adobe's Creative Cloud apps. It added that Sony's PlayStation 5 had also been targeted after a jailbreak led to a quick wave of emulators, and that Osmani said Anthropic would keep revising the rules.
Named in this story
People
- Addy Osmani
- confirmed the prompt change and explained the policy
Companies
- Anthropic
- changed the rules for Claude Code
- Adobe
- had parts of its Creative Cloud apps recreated
- Sony
- had its PlayStation 5 targeted after a jailbreak
Products and systems
- Claude Code
- was restricted from recreating existing video games
- Opus 5.5
- had its system prompt updated
- GPT-6 Astra
- was used by users to generate unofficial game ports
- Reverse Engineer Anything
- paired AI agents with reverse engineering
- Creative Cloud
- was partially recreated by a developer
- PlayStation 5
- became a target for emulators after a jailbreak
How the source tells it
The article used an alarmed, escalation-driven register, then softened it with a brief reassurance that legitimate game-making was still allowed.
- alarm casts the policy change as a response to a flood of cloning projects and a widening intellectual property dispute
- escalation frames the issue as moving from images and videos into software
- reassurance balances the restriction with a note that users can still build their own games