Discussion summary
Discussions highlight that Anthropic's classifiers for Fable are overly sensitive, limiting its usability, especially in areas like math and multi-turn conversations. Some users criticize the guardrails as too restrictive, while others defend Anthropic's safety measures.
What the discussion says
- Fable is underrated for personal advice, but its guardrails are too sensitive.
- Anthropic's safety measures may hinder Fable's functionality.
- Some users believe the sensitivity is necessary for safety.
- Critics argue the guardrails limit multi-turn discourse and math use.
- Supporters see safety as a priority over flexibility.
“Fable's guard rails are way too sensitive.”
“Anthropic's safety measures may hinder usability.”
Join the discussion
Write your take first — we'll ask for email only when you're ready to publish.
- Hacker News
- I've found in my current work on a security auditing harness and benchmarks, both Fable and Opus are useless. I recently switched to using GPT for Nelson and the security benchmarks I've been doing because Opus started refusing to do the work. I guess I probably could also use GLM or DeepSeek or MiMo, and I'll probably do some experiments to see the shape of all of their guardrails in this area soon, now that I see it's more than one model that behaves this way (Gemini in Antigravity also refuses any security auditing task, even as simple as "find security bugs").
I blogged about it: https://swelljoe.com/post/why-i-had-to-switch-to-gpt/
by SwellJoe - I've had good luck getting it to debug (and patch) a tricky WebRTC issue that had all the other models stumped. Sorry it didn't work on your problem, I guess?by ai_critic
- I'm curious what the state of alignment research is. My gut says this is basically impossible. People have different moral frameworks. Each individual probably has an inconsistent moral framework. Even granting perfect consistency, applying these typically requires some knowledge of reality. And these LLM / harness combos are turing complete.
So you don't know what it should do, you may not even know what you would do, you don't necessarily know what's happening, and can't predict what will happen. How do you align that?
Seems like these overly sensitive filters are responding to this difficulty.
by sobellian - I'm a medical physicist. I literally haven't been able to get Fable to answer a question I have written -- all of my work is verboten. I have however asked Claude Code (opus 4.8) to ultracode "a Fable oracle that <deals with the high level difficult problems> in a digraphed, clean content, isolated environment with a minimally scoped working codebase. Ask the model at the start and the end to report exactly what its version string is. If it is not claude-fable-5, stop the agent and refine the prompt until this changes"
It burns through tokens like anything but apparently Claude is much better at prompting Claude than I am.
Would I pay for it? God no. I'm still smarter than I am and it just will not work on my actual problems.
by azalemeth - I asked it a question about indoor carbon dioxide levels (wholly innocuous question), which it flagged as involving biology, therefore downgraded to Opus.
It's a pretty good strategy if they're hoping to fail as a business, I guess.
by ergonaught - Fable was refusing to patch vllm for me when trying to get mtp to work on r9700 gpus. Kept on bumping down to opus. Tried to really sanitize my prompts and everything but it seemed intrinsically prohibited from doing this sort of work. I guess it’s useful for making inane one shot games and websites, lol.by vardalab
- For anyone using these models for anything remotely sensitive, keep in mind that Anthropic says [0]:
> We retain inputs and outputs for up to 2 years and trust and safety classification scores for up to 7 years if your chat is flagged by our automated trust and safety systems as violating our Usage Policy.
And, since those automated systems apparently have a ludicrous false-positive rate, you should assume that your inputs and outputs are being retained for 2 years even if you are doing nothing that any reasonable person would consider to be problematic.
Oh, and they'll train on that data [1]:
> We will use your chats and coding sessions (including to improve our models) if:
>You choose to allow us to use your chats and coding sessions to improve Claude, learn more here
> Your conversations are flagged for safety review (in which case we may use or analyze them to improve our ability to detect and enforce our Usage Policy, including training models for use by our Safeguards team, consistent with Anthropic’s safety mission)
It appears that the usual controls (including for businesses) to prevent Anthropic from training on your data will not apply.
[0] https://privacy.claude.com/en/articles/7996866-how-long-do-y...
[1] https://privacy.claude.com/en/articles/10023580-is-my-data-u...
by amluto - This post can essentially be distilled down to: yes, Fable's classifier (which is meant to downgrade cybersecurity, biology, or jailbreak attempts to Opus 4.8) is definitely overly sensitive to the point of uselessness.
e.g. a colleague asked Fable to help create an simple app to help calculate the statistics for phase II and III trials. (Ignoring that such things already exist) it passed his request down to Opus, despite only being very marginally, tangentially, somewhat related to biology.
by mft_