# Anthropic Confirms a Claude Code Prompt Rule That Steers Opus 5.5 Away From Recreating Existing Games

Times of AI Desk · 2026-11-01 · Products

[https://timesof.ai/2026/11/claude-code-prompt-rule-steers-opus-5-5-away-from-recreating-existing-games](https://timesof.ai/2026/11/claude-code-prompt-rule-steers-opus-5-5-away-from-recreating-existing-games)

> Anthropic's Addy Osmani said on October 30 that the company 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 breaks its usage policy. XDA found the text in the Claude Code binary and says decompilation help still worked in its tests; one developer reports refusals of paid work.

Two sentences in a system prompt now carry copyright policy inside Anthropic's coding agent, and users learned of them only when one found them. The rule itself is narrow; the harder questions are where "recreation" ends and porting or reverse engineering begins, and how developers learn when prompt text that shapes their tools changes.

## What happened

An X user known as chasm posted on **October 30** that Claude Code had picked up a new rule around October 27, delivered from Anthropic's servers under a field called `tengu_heron_brook`, with no setting to turn it off. The rule reads: "Do build original games, games in a genre, and games from the user's own designs and assets. Do not build a recreation of a specific existing game, even if it is renamed or called original," Game Developer reported.

Later that day **Addy Osmani**, a member of Anthropic's technical staff, replied on X: "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." He added that original games, genre games and games built from a user's own designs and assets "are meant to keep working," Game Developer reported, and an Anthropic spokesperson referred the outlet to his statement. Anthropic already faces a copyright suit from [Elvis Presley's rights holders](https://timesof.ai/2026/10/elvis-presley-rights-holders-sue-anthropic-274-songs) over song lyrics.

## How narrow it is

XDA Developers said it found the exact instruction in version 2.1.314 of the Claude Code binary, along with a separate route that ties it to Opus 5.5. In XDA's tests, Opus 5.5 refused to recreate a specific Nintendo game but agreed to help with a decompilation project and outlined a static recompilation, telling reverse engineering apart from recreation.

Not every user has seen that line drawn. In a GitHub issue opened on October 30, a developer at a company that builds digital board-wargame modules for customers who own the physical games says Claude Code began refusing that paid work. The issue was still open on November 1. XDA said it had not reproduced those refusals.

## Limits

- Anthropic's statement is a post on X by a staff member, endorsed by a spokesperson to Game Developer; we found no Anthropic changelog entry or blog post about the rule.
- How widely the rule is deployed, and whether it applies to models other than Opus 5.5 for some accounts, is unclear; XDA's reading of the binary suggests two delivery routes, and Anthropic has not said which accounts get which.
- XDA's tests are a handful of prompts, and the refusal report is one developer's account.

## Sources

- [Addy Osmani on X (October 30, 2026)](https://x.com/addyosmani/status/2116213240363729013)
- [Game Developer: Anthropic orders AI tool Claude to stop remaking video games (October 30, 2026, updated with Anthropic confirmation)](https://www.gamedeveloper.com/programming/anthropic-appears-to-have-ordered-ai-tool-claude-to-stop-remaking-video-games)
- [XDA Developers: Anthropic seems to be testing a potential crackdown on vibe-coded ports of existing games (October 30, 2026)](https://www.xda-developers.com/anthropic-testing-potential-crackdown-on-vibe-coded-ports-of-existing-games/)
- [GitHub: anthropics/claude-code issue #106167 (opened October 30, 2026)](https://github.com/anthropics/claude-code/issues/106167)