Anthropic redeploys Claude Fable 5 globally after updating safety classifiers to block a vulnerability exploit in 99% of cases

VIEWS7.1KREPLIES19

So uh, Fable will be useless?

Apparently coding work will fall back to Opus.

Claude Fable 5 will be available again globally tomorrow.

After a series of productive conversations with the US government, we're redeploying the model with a new set of classifiers to target and block more cybersecurity tasks. In the near term, some routine tasks like coding and debugging will fall back to Opus 4.8. We’ll continue to refine these classifiers over the coming weeks to reduce false positives and better distinguish genuine misuse from legitimate requests.

We’ve also begun drafting a consensus framework—with Amazon, Microsoft, Google, and other Glasswing partners—for assessing the severity of AI jailbreaks and how AI developers should respond to them. We invite other industry partners and model providers to join us in this effort.

Finally, we’re scaling up our collaboration with the US government on model testing and safeguards. This will include pre-release access to models and safeguards for evaluation, information sharing on jailbreaks and misuse, and dedicated resources for joint research.

Thank you to our users for your patience, and to our partners across the government, industry, and the research community who worked alongside us to make Fable 5 available again.

Read our full blog: https://www.anthropic.com/news/redeploying-fable-5

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Thariq@trq212

Have seen some questions about the updated classifiers and wanted to clarify.

As with the original classifiers, a small fraction of routine coding and debugging tasks will be flagged and fall back to Opus.

We're excited for guys to get access back tomorrow.

Anthropic@AnthropicAI

Claude Fable 5 will be available again globally tomorrow.

After a series of productive conversations with the US government, we're redeploying the model with a new set of classifiers to target and block more cybersecurity tasks. In the near term, some routine tasks like coding and debugging will fall back to Opus 4.8. We’ll continue to refine these classifiers over the coming weeks to reduce false positives and better distinguish genuine misuse from legitimate requests.

We’ve also begun drafting a consensus framework—with Amazon, Microsoft, Google, and other Glasswing partners—for assessing the severity of AI jailbreaks and how AI developers should respond to them. We invite other industry partners and model providers to join us in this effort.

Finally, we’re scaling up our collaboration with the US government on model testing and safeguards. This will include pre-release access to models and safeguards for evaluation, information sharing on jailbreaks and misuse, and dedicated resources for joint research.

Thank you to our users for your patience, and to our partners across the government, industry, and the research community who worked alongside us to make Fable 5 available again.

Read our full blog: https://www.anthropic.com/news/redeploying-fable-5

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LIKES70

Thariq@trq212

@vikassabbi you should sleep

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Anthropic@AnthropicAI

Claude Fable 5 will be available again globally tomorrow.

After a series of productive conversations with the US government, we're redeploying the model with a new set of classifiers to target and block more cybersecurity tasks. In the near term, some routine tasks like coding and debugging will fall back to Opus 4.8. We’ll continue to refine these classifiers over the coming weeks to reduce false positives and better distinguish genuine misuse from legitimate requests.

We’ve also begun drafting a consensus framework—with Amazon, Microsoft, Google, and other Glasswing partners—for assessing the severity of AI jailbreaks and how AI developers should respond to them. We invite other industry partners and model providers to join us in this effort.

Finally, we’re scaling up our collaboration with the US government on model testing and safeguards. This will include pre-release access to models and safeguards for evaluation, information sharing on jailbreaks and misuse, and dedicated resources for joint research.

Thank you to our users for your patience, and to our partners across the government, industry, and the research community who worked alongside us to make Fable 5 available again.

Read our full blog: https://www.anthropic.com/news/redeploying-fable-5

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Aaron Levie@levie

Things seem to be ending up in a better spot with Fable, and presumably GPT-5.6 next. What we have now is the initial precedent for what frontier model releases (or at least those that have significant coding and cyber capabilities) could look like going forward. This would presumably apply to bio and other categories of risk that have been identified by AI safety groups.

From the Anthropic post:

“3. A shared industry framework. Although we have reached a constructive resolution, these events have made clear that the industry needs a consistent way to assess and fix potential “jailbreaks” of AI models (techniques that bypass a model’s safeguards).2 A shared standard for judging the severity of a given jailbreak would help AI developers triage new findings as they arise, launch highly-capable models with greater safety, and communicate the level of risk consistently to government and industry partners. Together with Amazon, Microsoft, Google, and other Glasswing partners, we’ve started to develop such a framework, and we outline it below.

4. Deeper government collaboration. We’re also strengthening our level of collaboration with the US government on new pre-release testing, information sharing, and research collaboration. We describe this deeper collaboration in the final section.”

It’s been a messy process to get here, but at least there’s some semblance of a framework that could be practical. The only note of caution here would be that there’s a lot of subjectivity that goes into various risks and their actual levels of exploitability in practice. We’re likely going to be living with a framework that requires heavy judgment and back and forth between labs and the government for major releases.

The best we can hope for is that this is a relatively efficient process, and hopefully has ways of being sped up for incremental version updates in models. It would be a bad outcome if every release after this level of threshold of capability required the same review process, and we don’t get the same rate of breakthroughs we’ve been seeing.

Anthropic@AnthropicAI

Claude Fable 5 will be available again globally tomorrow.

After a series of productive conversations with the US government, we're redeploying the model with a new set of classifiers to target and block more cybersecurity tasks. In the near term, some routine tasks like coding and debugging will fall back to Opus 4.8. We’ll continue to refine these classifiers over the coming weeks to reduce false positives and better distinguish genuine misuse from legitimate requests.

We’ve also begun drafting a consensus framework—with Amazon, Microsoft, Google, and other Glasswing partners—for assessing the severity of AI jailbreaks and how AI developers should respond to them. We invite other industry partners and model providers to join us in this effort.

Finally, we’re scaling up our collaboration with the US government on model testing and safeguards. This will include pre-release access to models and safeguards for evaluation, information sharing on jailbreaks and misuse, and dedicated resources for joint research.

Thank you to our users for your patience, and to our partners across the government, industry, and the research community who worked alongside us to make Fable 5 available again.

Read our full blog: https://www.anthropic.com/news/redeploying-fable-5

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Andrew Curran@AndrewCurran_

'For models that materially advance the capability frontier in areas relevant to national security, we will provide designated government partners with expanded early access to both the models and the safeguards that accompany them.'

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dax@thdxr

@trq212 a lot of my prompts were being downgrade and when i checked logs it said TOO_DUMB_TO_NEED_FABLE what was happening there?

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Andrew Curran@AndrewCurran_

Fable 5 will be available for Pro, Max, Team, and select Enterprise plans tomorrow and will be included for up to 50% of weekly usage limits through July 7, after that it will be available via usage credits.

Anthropic is partnering with the US government on frontier AI security.

Anthropic@AnthropicAI

Claude Fable 5 will be available again globally tomorrow.

After a series of productive conversations with the US government, we're redeploying the model with a new set of classifiers to target and block more cybersecurity tasks. In the near term, some routine tasks like coding and debugging will fall back to Opus 4.8. We’ll continue to refine these classifiers over the coming weeks to reduce false positives and better distinguish genuine misuse from legitimate requests.

We’ve also begun drafting a consensus framework—with Amazon, Microsoft, Google, and other Glasswing partners—for assessing the severity of AI jailbreaks and how AI developers should respond to them. We invite other industry partners and model providers to join us in this effort.

Finally, we’re scaling up our collaboration with the US government on model testing and safeguards. This will include pre-release access to models and safeguards for evaluation, information sharing on jailbreaks and misuse, and dedicated resources for joint research.

Thank you to our users for your patience, and to our partners across the government, industry, and the research community who worked alongside us to make Fable 5 available again.

Read our full blog: https://www.anthropic.com/news/redeploying-fable-5

2h743132

Rhys@RhysSullivan

@AndrewCurran_ Damn that sucks

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Andrew Curran@AndrewCurran_

'Our hope is that this collaboration, along with our proposed consensus industry framework, will serve as the basis for systematic rules for the whole industry—and even offer the beginnings of a template for effective global coordination on the risks and benefits of AI. These rules should be codified in strong regulation and applied equally across frontier model developers.'

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404prophet@lightscaner

Lol has to be a joke. Here you can have it but only for a week and only up to half of your usage and dont bother debugging. What the hell y'all. Scrape the whole internet then sell it back to us poorly. @AnthropicAI is a threat to society and anyone who works there should be shamed.

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Thariq@trq212

@thdxr didnt think you would read the logs tbh

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Sam L@samelldev

@AnthropicAI Fable 5 is great.

But still reserving Mythos for government/select few isn't right. We all need to be able to perform defensive vulnerability checks and fixes, and Fable doesn't let us do anything security related

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Finny@FinnyTalks

@trq212 Will it be transparent and let users know that they have fallen back to Opus, or will this just happen without warning and clarification.

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Owen Carey@owenthcarey

@AnthropicAI “In the near term, some routine tasks like coding and debugging will fall back to Opus 4.8.”

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Thariq@trq212

And as we say in our blog, we're continuing to refine these safeguards to better distinguish genuine misuse from legitimate requests and reduce false positives.

Thariq@trq212

Have seen some questions about the updated classifiers and wanted to clarify.

As with the original classifiers, a small fraction of routine coding and debugging tasks will be flagged and fall back to Opus.

We're excited for guys to get access back tomorrow.

1h497121

Brian Roemmele@BrianRoemmele

Ahhh the fine print of the Fable.

All the pro Anthropic folks are being played again.

Pay for the Fable and get the Opus.

The AI shell game.

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Robert Scoble@Scobleizer

“Some” coding tasks will fail back:

I will pull my “feels like having a World Cup goal taken away” post because it isn’t accurate.

Anthropic@AnthropicAI

Claude Fable 5 will be available again globally tomorrow.

After a series of productive conversations with the US government, we're redeploying the model with a new set of classifiers to target and block more cybersecurity tasks. In the near term, some routine tasks like coding and debugging will fall back to Opus 4.8. We’ll continue to refine these classifiers over the coming weeks to reduce false positives and better distinguish genuine misuse from legitimate requests.

We’ve also begun drafting a consensus framework—with Amazon, Microsoft, Google, and other Glasswing partners—for assessing the severity of AI jailbreaks and how AI developers should respond to them. We invite other industry partners and model providers to join us in this effort.

Finally, we’re scaling up our collaboration with the US government on model testing and safeguards. This will include pre-release access to models and safeguards for evaluation, information sharing on jailbreaks and misuse, and dedicated resources for joint research.

Thank you to our users for your patience, and to our partners across the government, industry, and the research community who worked alongside us to make Fable 5 available again.

Read our full blog: https://www.anthropic.com/news/redeploying-fable-5

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vikas sabbi@vikassabbi

@trq212 Is it gonna be available tonight? or can I go to sleep?

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Phil Chen@philhchen

Here's a note I posted to the team today about how I think about token budgets going forward:

Spending tokens is easy. Without even trying hard, I've been able to spend ~$2k / day in tokens with GPT 5.5.

Saving tokens is easy. Many tasks don't actually need frontier intelligence if we just use our own intelligence upfront (fixing a UI nit is not Fable-level if we prompt precisely). Spending more time and tokens upfront towards a logically sound design saves time and tokens later.

Internally, we will dynamically allocate token compute to people through a simple request system. For each project, request either $200 (1 day project) or $2000 (1 week project) in token compute if you think it is Fable-worthy. These numbers can change.

In the age of abundant intelligence, we are all becoming capital and time allocators. We should have best-in-class intuition on how much intelligence we get per unit of capital and/or time.

Anthropic@AnthropicAI

Claude Fable 5 will be available again globally tomorrow.

After a series of productive conversations with the US government, we're redeploying the model with a new set of classifiers to target and block more cybersecurity tasks. In the near term, some routine tasks like coding and debugging will fall back to Opus 4.8. We’ll continue to refine these classifiers over the coming weeks to reduce false positives and better distinguish genuine misuse from legitimate requests.

We’ve also begun drafting a consensus framework—with Amazon, Microsoft, Google, and other Glasswing partners—for assessing the severity of AI jailbreaks and how AI developers should respond to them. We invite other industry partners and model providers to join us in this effort.

Finally, we’re scaling up our collaboration with the US government on model testing and safeguards. This will include pre-release access to models and safeguards for evaluation, information sharing on jailbreaks and misuse, and dedicated resources for joint research.

Thank you to our users for your patience, and to our partners across the government, industry, and the research community who worked alongside us to make Fable 5 available again.

Read our full blog: https://www.anthropic.com/news/redeploying-fable-5

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Anthropic redeploys Claude Fable 5 globally after updating safety classifiers to block a vulnerability exploit in 99% of cases

Story Overview

Routine coding shifts temporarily

Partners eye a shared jailbreak scorecard