Anthropic technical staff member Addy Osmani said on October 30, 2026, that Anthropic had added two sentences to the Claude Code prompt for Opus 5.5. The instruction is meant to steer Claude Code away from recreating a specific existing game. Osmani said original games, genre games, and projects built from users’ own designs and assets are meant to keep working.
What the instruction targets
The stated aim is to discourage recreating a particular existing game. Ars Technica reported that the instruction also covers a recreation renamed or presented as an original. Osmani described the change as a prompt instruction for Claude Code on Opus 5.5.
What a reported build and one user’s test add
Ars Technica reported that XDA found the instruction in Claude Code binary version 2.1.314, released October 30, 2026. That is a reported client-build finding, separate from the Opus 5.5 model named in Osmani’s statement.
Reddit user u/vinishkapoor reported trying nine prompts on each of versions 2.1.312 and 2.1.316 with Opus 5.5, for 18 runs. The user said original-game, genre, own-design, bug-fix, and reference-mechanic tasks worked on both versions. On the newer version, a request to recreate Tetris produced a different game; a Flappy Bird request produced a game on both versions. The user’s prompt-test account
