GoKawiilWell. I wasn’t quite planning to write this evening, since it’s Friday and Fridays are when I like to code, and when I say code I mean ‘let the agent code while I watch soccer with my friends.’ Recently I’ve been making some fun html games. I actually have another draft post in the barrel about how I think we should see a resurgence of the ‘flash game’ renaissance because it has become so much easier to make fun little games with AI tooling. But in the middle of me thinking about how to make my shitty backrooms-themed shooter play a bit better, the agent went ‘Sorry! This model doesn’t exist any more!’
What the fuck?
My first thought was that I needed to re-login. I run a ton of agents in parallel most of the time, so my instinct was that this was just a really really weird limit error. I vaguely knew that Anthropic was thinking about pulling Fable off the subscription plans so I switched to the API. Still nothing.
My team built a custom rust agent client, it’s pretty great. But my next thought was ‘o shit the harness bricked’, and I started poking around in Rust, which is a language I barely know even though I’ve ostensibly written tens of thousands of lines of code of it. At which point my friend went ‘the government banned fable.’
What the fuck?
But it’s true.
The US Gov directed Anthropic to disable access to Fable and Mythos to any foreign national anywhere in the world, including those in the US, including Anthropic employees. This is an impossible ask, and the Government knows it, so Anthropic has disabled all access to Fable/Mythos.
We are complying with the government’s legal directive and are removing access to Fable 5 and Mythos 5 for all users. However, we disagree that the finding of a narrow potential jailbreak should be cause for recalling a commercial model deployed to hundreds of millions of people.
We have reviewed a report that we believe is the basis of the government’s directive and validated that the level of capability displayed there is widely available from other models (including OpenAI’s GPT-5.5), and is used every day by the defenders who keep systems safe. We will share more details over the next 24 hours.
We received the directive from the government today at 5:21pm (ET). The letter did not provide specific details of its national security concern. Our understanding is that the government believes it has become aware of a method of bypassing, or “jailbreaking” Fable 5. We reviewed a demonstration of this specific technique being used to identify a small number of previously known, minor vulnerabilities. These vulnerabilities all appear relatively simple, and we have found that other publicly-available models are able to discover them as well without requiring a bypass.
... continue reading