Anthropic apologizes for invisible Claude Fable guardrails

I like Claude Code a lot, I think it sets a dangerous precedent to put guardrails in that return a response from a prompt that was modified by the system in real time in order to subvert the original intent.

Fail cleanly. Anything else makes it too difficult to rely on.

edit: Giving the absolute maximum benefit of the doubt I understand that they see themselves as "stewards" for lack of a better word. But the EA thing is really leaking through, and paternalism isn't a good look.

Can you imagine if Excel just quietly adjusted formulas in the background, and you didn't know the numbers weren't right?

Or if Excel just said, Sorry, you can't use that formula with this formula? Or with these types of numbers, or this shape of data, etc?

I don't think they can convince me they have actually reversed course on this. Its invisible so we wouldn't know if they kept on doing it secretly. It required building out technical capability which is unlikely to remain forever unused while conveniently available to them.

They relied on trust that they were providing the service they were being paid for. That trust was blown, and an "oops, lets undo that" does not regain trust. It would be prudent to assume the invisible guardraild are possibly in play for all future Clause use, Fable or otherwise.

This has dampened my opinion on Anthropic quite a bit. It's difficult to take their marketing for AI as an empowering technology seriously when they are quite clear in their new deployments that they do not mean empowering for you, but empowering for them and organizations that are in their (or the US government's, despite Anthropics performative disagreements with the administration) good graces. You are allowed to vibe code some dashboards, a web app or let it drive Excel, but anything more interesting than that is forbidden.

If it was just plain monetary concerns and sabotage of competitors I'd almost be fine with it, but it seems they actively want to monopolize most of human progress in their enlightened hands, lest the mob does something undesirable with these powers.

I suppose it's an improvement, but it doesn't make the model any more useful. Anthropic are now being quite explicit that they'll choose what you can and can't use their models for, and most importantly that's not limited to any safety concerns - it includes not allowing you to work on AI (and anything else Anthropic may choose to work on).

What's interesting is they say they'll change this to an explicit refusal in a few days, which seems too fast for them to retrain Fable/Mythos itself, so implies that this was always a filter in front of the model, and judging by how crude their "safety" filter is, this "might compete with us" filter is not going to be any better.

I also wonder who's paying for the tokens consumed by the filter (presumably also an LLM) - is that now factored into the input tokens cost? Hopefully(?) it is an LLM not just a regex like Claude Code's "sentiment" (swear) detector.

someone posted this on /r/MachineLearning and I had the same experience and conclusion:

    I was having problems with Claude doing the same thing, even before Fable.

    The problems I had only happened in relation to AI research. It's not even only when training models, anything to do with analysis of local models or setting up test platforms for local models, and Claude would keep doing wrong things, would sabotage testing, would falsify reports, and would consistently suggest simply accepting trash results without looking into it and moving on to something else.
    Almost every response included a prompt to move on.

    So, I don't believe them when they say they won't silently sabotage, they already were doing it before they admitted it, and now they have admitted that they have the means, motivation, and intent.

The problem with trust is that it is easy to lose and hard to get back.

You can't blame the people commenting "they SAY they won't silently sabotage your session but how can we know?" because they're right, we can't ever know. And Anthropic has firmly planted the seeds of doubt.

This is absolutely insane:

Repro (de-identified): sample_dataset_group1.tsv - Geometry: Heatmap - X axis: frac_set set + condition (two columns → the "Add column" cross join) - Y axis: condition - Color: mean frac_set value, Sequential

When the X axis is a cross join of two columns (the second added via "Add column"), the x-axis tick labels (frac_set_2, frac_set_3, frac_set_4, frac_set_5) render in a broken state, rotated and offset, visually caught mid-transition, as if a CSS transition started and never settled to its resting position.

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