The classifiers Anthropic puts in front of Fable are too zealous

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• Hacker News
• Fable is great. Very underrated on just personal life advice.
  by LZ_Khan
• This honestly just reads as “this model failed exactly where the company said it would but I’m very special and deserve special treatment rather than the same overactive guardrails I and everyone else were told we would get.”
  by junebash
• When did Anthropic say you couldn't use it for math?
  by charcircuit
• I just think that Anthropic's usage of the word "classifier", which implies a minimum level of intelligence, was very misleading. Fact is, you cannot use Fable for anything remotely connected to even elementary school biology or medical topics. There is no attempt whatsoever to distinguish between legitimate and dangerous tasks, except an extremely broad and non-specific rejection of anything related to security or biology.
  by Sol-
• I wonder how this plays into Anthropic's legal holds:

  The retention schedule behind it:

  Deleted conversations: removed from your chat history immediately, but kept on back-end systems for up to 30 days before permanent deletion. Flagged inputs and outputs (Usage Policy violation): retained up to 2 years. Trust-and-safety classification scores (on flagged sessions): retained up to 7 years. API logs: 7 days by default (as of September 14, 2025), extendable to 30 days via a DPA. Zero Data Retention (qualifying enterprise): inputs and outputs aren't stored after the API response returns, though safety classifier results are still retained even here.

  by claudenoforget
• update: Anthropic has not published the retention treatment of routing metadata, in particular whether a reroute counts only as caution (the 30-day safety-monitoring floor) or as a Usage Policy violation flag (the 2-year content and 7-year score horizons in Part I). That distinction is legally consequential, because a flagged Fable session could persist far longer than 30 days. The classifier's internal decision logic is also deliberately undisclosed.
  by claudenoforget
• Terrible title. Should be "Fable's guard rails are way too sensitive", which I don't think you can really blame Anthropic for. They likely had to whack them way up so it would block whatever trivial stuff got demoed to the government.

  I would expect them to dial down the sensitivity in a few months when nobody is looking.

  by IshKebab
• > I would expect them to dial down the sensitivity in a few months when nobody is looking.

  I don't think it's as much when no one is looking, but instead when the broad industry SOTA, particularly Chinese models that the US government has zero control over, has advanced enough that it's security theatre restricting it.

  by llm_nerd
• >which I don't think you can really blame Anthropic for.

  on the contrary, you can, and you should. their greasy effective altruist had always been by far the loudest proponent of the `safety` theater.

  by vlian2088
• I goddamn hate fable for anything but vibecoding.

  It's generally a major downgrade in acting like an assistant.

  I don't know what's wrong but it is just bad at multi turn discourse even on a limited amount of content with no MCP or bash calls of any sort.

  The thing that makes me mad is how stubbornly confident it is even whets wrong.

  I have to tell it many times to actually re read the conversation as it even insists I said something else.

  It's like it had a scratchpad where it has some summarized bullet points which it fills of made up content.

  I'm so confused. On one side I like to connect it to honeycomb/otel logs and I can see it figures out difficult bugs in the code better than other models.

  On some others I feel I'm assisting at a continuos disaster and consistent degradation since Opus 4.6, it's a tragedy.

  I'm more and more the assistant to a capable, yet confidently stubborn and wrong LLM.

  by epolanski
• Gee, ya think?? LOL
  by pmarreck
• It's almost like every release is just basically advertising.
  by talideon
• I have only really used Fable as a final pass on something. A "Take a look at everything we did so far, and make sure we didn't forget something" kind of review prompt.

  But it is a huge waste of money for most coding tasks. Opus is still overkill most of the time, too.

  by RIMR
• > But it is a huge waste of money for most coding tasks.

  The key is not to indiscriminately use the most powerful/expensive model you can for everything. When you use it for what it's uniquely suited for and ask it to spawn subagents using Opus and Sonnet based on what tasks need, you'll get better results at a reasonable cost.

  by CharlesW
• I have used Fable to the full extend of the 20x subscription's weekly limit, for all development tasks on my iOS project.

  It was working better than Opus for me. It more often implemented features well on the first try, where Opus needs a few rounds of improvements to reach a passable result.

  I am not sure why it would be a waste of money "for most coding tasks", and how you could conclude so with any confidence when you did not even really use it aside from final review passes.

  by user43928
• > Nonetheless, that is not want I wanted to focus my thoughts on here.

  Typo second paragraph, 4th line. I think you meant "what"

  by dbvn
• Fast forwarding a year, if such censorship is in our future for all new closed models, then switching to open models will be the only way out.
  by OutOfHere
• They're not just "too zealous", they're ludicrous.

  I've had it reject looking at pages served from my local network because it "can't find it with my search tool" and had "ethical concerns about consent for access".

  The People's AI Concern Front has gotten the classifier they want, and it's made Claude hilariously useless. I am waiting with bated breath for their next set of revenue numbers. (And happily hand my money to competitors instead)

  by groby_b
• I totally agree. I have been a Claude fanboy for a while now, but Fable woke me up, and I am currently looking for alternatives.

  I don't care how capable it is, if it's going to treat me like it's babysitting a terrorist, it can eff off.

  Plain and simple.

  by bronlund
• Worst title ever. For once I feel the HN title should NOT match the article.
  by lherron
• It seems like Opus is a lot slower than Fable, or it’s throttled
  by benguild
• I asked about logging in national forest land and it triggered the safety classifier. Logging is a cybersecurity risk, I suppose.
  by ashdksnndck
• I couldn't even get it to help me write an email, because that email was to a pentesting company!

  However when it's happy to do the task, its relatively fantastic.

  by PUSH_AX
• Made a similar observation few days ago! https://news.ycombinator.com/item?id=48778446

  I'm a bioinformatician

  by iqbal1980
• There is a bacterial outbreak and I asked if it was possible that's what made my wife sick and it downgraded.
  by base698
• I've had fable disengage on anything related even tangentially to "biology"

  Even questions about like my heartrate nunbers while running seem to run into the bio weapon filter

  by karma_daemon
• I made the same observation few days ago, follow bioinformatcian here https://news.ycombinator.com/item?id=48778446
  by iqbal1980
• The classifier for biology is so broad it makes me wonder what kind of stuff mythos was generating. Anthropic is known to be a bit dramatic, but they wouldn't have released something this broad unless they saw the model cross a significant threshold that scared them.
  by swalsh
• Do we think that someone at Anthropic, OpenAI, the government... has access to SOTA models without censorship? "How do I build an effective weapon?", "How do I effectively control the masses?"...

  It's very concerning that we get the nerfed models but you know that somewhere, people with a lot of resources have access to the raw, uncensored, probably more powerful models. The sprint toward AGI looks even more dangerous when you think about who will be gaining access to it first. I do believe the goal is to pull away from the rest of humanity in a near trans-humanistic state. Are we ready for that and how do we counter it?

  by slowin
• Yes. Mythos is almost exactly that. Willing to do in depth vulnerability and POC work.
  by bitexploder