Anthropic has introduced new restrictions in Claude Code, its AI-powered coding tool, blocking the ability to recreate specific existing video games, including Minecraft and Candy Crush. The change, internally codenamed "tengu_heron_brook," instructs the model to refuse attempts to clone someone else's game, even if the user renames it or describes the project as entirely original.

Two Sentences That Changed the Rules

As Addy Osmani, a member of Anthropic's technical staff, explained, the change was minimal technically but significant in practice. "We 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 violate intellectual property rights goes against our usage policy," Osmani said, as quoted by WION.

In practice, this means Claude Code now refuses prompts like "make a remake," "clone," or "recreate" a specific title, even recognizing attempts to get around the restriction by renaming the project. The model still allows building games from scratch, in popular genres and with original assets, but draws the line at directly copying the recognizable mechanics, graphics, or music of a specific title.

Why Minecraft Specifically

The choice of Minecraft as an example title isn't random. Mojang's game is one of the most frequently "cloned" projects on the internet: the simplicity of its cube-based building mechanics and world generation has for years encouraged developers, including those using AI assistants, to create unauthorized copies or very close imitations. Anthropic points out that video games contain copyrighted elements: original characters, graphics, music, code, and gameplay solutions, and recreating them without a license infringes on creators' rights.

From the perspective of Polish players and mod creators, this is a signal that the line between "inspiration" and "copy" in the generative AI era is becoming the subject of increasingly concrete regulations from tool providers, not just legal guidelines or licensing agreements from Mojang and Microsoft.

The decision fits into a broader pattern of Anthropic's behavior regarding intellectual property. The company previously agreed to a settlement in a copyright lawsuit related to using protected books to train its language models, for 1.5 billion dollars. The new restrictions in Claude Code can therefore be read as an attempt to avoid further legal disputes, this time from the video game industry, before the problem escalates to a similar scale.

VideoCardz reported that some developers are reporting blocked projects that, in their view, weren't an attempt to clone a specific game but simply used mechanics typical of the genre, such as procedural world generation or crafting systems. This raises the question of where exactly the line lies between copyright protection and excessively restricting creativity that draws on popular design patterns.

What This Means for Mod and Map Creators

The restriction applies only to the Claude Code tool and how the model responds to requests to recreate specific games from scratch. It doesn't directly affect existing mods for Minecraft legally created using the official modding API, nor building maps and servers within Java Edition. Creators using AI to write plugins, scripts, or generate textures in their own data pack projects shouldn't notice a difference, as long as they're not asking the model to recreate Mojang's game itself.

The problem mainly affects people who would want to use Claude Code to create an unauthorized clone of a game engine or its recognizable elements from scratch, which has always carried legal risk regardless of the development tools used.

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