Anthropic confirms new Claude Code limits to prevent game cloning, users report blocking reverse engineering tasks

Anthropic's recent move to have Claude Code deny video game cloning and possibly reverse engineering efforts has come under heavy fire from the software development community. Hot on the heels of Friday's report on the matter, an Anthropic employee responded to the tweet with the purported rule update with a direct statement confirming that the firm added guardrails to Claude Code to prevent game recreation.

In the full tweet, which you can read below, Addy Osmani says that "[Anthropic] 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 [its] usage policy." He goes on to state that work on original games is meant to continue working, and that Anthropic is iterating on the rules to try and "strike the right balance."

There's no telling what those sentences might be, though given Osmani's choice of words, it's possible that said sentences are indeed what X user Chasm posted a screenshot of: "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 renamed or called original."

In our previous report, we had already linked to recent issues raised at Claude Code's own GitHub repository, comprised of users complaining that the AI assistant was refusing to work on their games or on reverse-engineering tasks. As far as we can ascertain, it appears the game-related blocking is limited to the combination of using Claude Code and the Opus 5.5 model. Should that prove true, then users should be able to sidestep the limitation by calling upon Opus using another harness like Ollama or forwarding specific requests through a wrapper of some sort.

Regarding the blocking of reverse engineering, we have received direct confirmations. The first comes from our own alumnus Jarred Walton, who was trying to run checks on the software he's developing. He notes that such work had been performed with no issue until yesterday, October 31, and that switching to Opus 4.8 let him continue his work.

Walton theorizes that Anthropic may have added a new rule to Code specifically for reverse-engineering. Considering that timing, plus the fact that other reports of refusals all popped up around the last week, may indicate that the company could be fiddling with cybersecurity-related rules in the same manner as they are for video game-related content.

We also received screenshots from a staffer's direct acquaintance, who asked Opus 5.5 (via Code) to try and reverse engineer a product activation, a request that likewise triggered safeguards. Meanwhile, notices that Claude Code appears to block reverse-engineering continue to mount, now with a Redditor allegedly having their account suspended, and then reinstated, over using Opus 5.5 and Reverse Engineer Anything. The company has an ongoing Cyber Verification Program, in which only approved entities get access to the full set of frontier models' cybersecurity capabilities.