Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Claude Fable 5.1 and Claude Mythos 5.1

anthropic.com

Post reply on HN
Print view View original

611–620 of 1001 posts

Re: Claude Fable 5.1 and Claude Mythos 5.1

#611

Post by ed-is-ai »

echelon wrote: post #149
PedroBatista wrote: post #125

Earlier quoted context omitted.

This post and comment makes me believe "science" is the new "code" for Anthropic now that the code advantage is mostly gone and lost for OpenAI, ie. they got much better and Claude become significantly worse over these months.

IMO, Codex is worse than Claude with Fable. At least at Rust. That said, the open source models are not bad and I'm looking forward to more tools and products built on top of them. Code review, security review, etc. Anthropic needs to change how it treats users though. I'm increasingly put off by Dario, the rug pulling, the lies, and the attempts to regulate open weights. I'm going to bail if this doesn't change. The…

The big issue I have with Fable is this. From the Anthropic email announcing Fable 5.1. So basically they're giving us a Ferrari, which will point blank refuse to do certain stuff - forcing us to go out in our Mustang. Their choice, not ours

"Safeguards and automatic fallbacks (beta): Fable 5.1’s biology and cybersecurity classifiers block fewer benign requests and now permit vulnerability finding in source code. Blocked requests return an error and are not charged to you. On the Messages API, opt in to fall back to another model so users get a response instead of an error. We recommend Opus 5 for biology and Opus 4.8 for cybersecurity. In Managed Agents, fallback is built in."

Re: Claude Fable 5.1 and Claude Mythos 5.1

#612

Post by Lucasoato »

Someone1234 wrote: post #92
tarr11 wrote: post #35

“ Claude Fable 5.1's writing is generally a step up from earlier Claude models, with fewer stock phrases and less unexplained jargon. In some cases, though, its prose is denser than Claude Fable 5's: sentences run longer and there are fewer paragraph breaks.” I cancelled my pro max Claude subscription last week; codex is much more succinct. I am curious if this is getting better. I don’t think Anthropic realizes that…

One thing I've noticed and HATE, is that when you increase thinking-effort, that seemingly increases response-length. Meaning that X.High is longer than High, which is longer than Medium, etc. Which is kind of the inverse of how people work; a really smart person can condense difficult ideas into simple[r] terms. Whereas people who struggle speak a lot but say very little. High/X.High do seem to deliver better qualit…

“I have made this letter longer only because I didn’t have the time to make it shorter.” - Blaise Pascal

Re: Claude Fable 5.1 and Claude Mythos 5.1

#613

Post by physix »

zahlman wrote: post #165
velcrovan wrote: post #121

Earlier quoted context omitted.

I have a pet theory that the Opus prose style/smell we all have grown weary of is due at least in part to the models writing more for themselves and each other than for humans. They're packing lots of signal into fewer words and they don't care if it sounds cringe because it works better as glue in long-running tasks. I'm also thinking of the 2017 novel "Void Star" where AIs who operate everything have long since lef…

> They're packing lots of signal into fewer words There's a huge difference between the kind of prose you see in final output vs CoT windows. The final output is very much not what I'd call "packing lots of signal into fewer words" (aside perhaps from "Claude-isms" being easy enough to scan for if for some reason you actually wanted to scan for them, which other agents might want to for all I know); and if agents are…

I've been cleaning up AI generated system/software design and architecture docs for an agentically engineered application, to translate that dense AI-speak into a clear human-readable form, cross checking it all against the actual codebase.

When I read the translated version, I felt a flush of relief, because I finally could confirm that it built the right thing and properly implemented the requirements.

I then asked in a fresh session which version was better for it as a reference for future work. It unequivocally voted for the human readable form, and gave it's reasoning with specific examples why.

So, I have a hunch that this "packing of lots of signals into fewer words" isn't really better. The incomprehensible prose just makes us think it knows what it's doing, like some mysterious magic that is only smoke and mirrors.

Re: Claude Fable 5.1 and Claude Mythos 5.1

#616

Post by NewsaHackO »

johnsmith1840 wrote: post #398
GodelNumbering wrote: post #139

The price reduction comes from the cache read pricing falling from $1/M to $0.25/M, which means that Fable 5.1 now costs half of Opus's cache read costs ($0.5/M). This gives a lot of credit to the theory that Anthropic did not get much bite on Fable at its original pricing, which in turn likely places a ceiling on LLM pricing in general. Interestingly also, if you take away terminal-Bench-Science 0.1 results, it is h…

I'm a heavy user and fable is great the #1 reason I stopped using it was the horrible safegaurd filter. I found sol close enough in capability and have only been blocked when my request was an obvious offensive cyber work. Fable blocked me on almost everything. Optimizing a OS build? -> block Securing a container -> block 60% is nowhere near enough for that safegaurd system. This just means I am going to be blocked h…

Do you have the prompt for these? I ask because I have recently asked Fable's help with hardening a docker container (custom dev container CC sandbox) and it didn't get triggered on it at all.

Re: Claude Fable 5.1 and Claude Mythos 5.1

#617

Post by adastra22 »

olirex99 wrote: post #355
adastra22 wrote: post #301

Earlier quoted context omitted.

As someone working in science, this belief confuses me. How (by what means) do you think Fable 5.1 will be able to make further progress in scientific domains? The problem with science is that there is no agentic harness. The agent can't test things. At best it can hallucinate something and ask if that hallucination "makes sense", but this doesn't work in science.

I suggest you to give a look to the MCP protocol for hardware that is being proposed by Anthropic. The hardware will be the next harness of LLMs, they will be able to operate machines to reinforce their theories. I still think that a major problem is that biological processes are not “fast” as coding, but they are verifiable. If during post processing we are able to give enough harness to test and verify this kind of…

The field I'm in requires millions of dollars of very sensitive (fragile) capital equipment, and latencies measured in weeks and months. Agents tend to move fast and break things, which matters less when you are writing code under version control.

Re: Claude Fable 5.1 and Claude Mythos 5.1

#618

Post by anthonyrstevens »

tripleee wrote: post #527
jbs789 wrote: post #435

Earlier quoted context omitted.

and yet we still have people saying the rate of change is increasing my view is we had a leap over the last fe years and it's tapering off. this is fine, but for the IPOs

We had a leap because of the introduction and refinement of agents - the rest has been minor

I've been using the same agent for 15 months. I think this statement is laughably wrong.

Re: Claude Fable 5.1 and Claude Mythos 5.1

#619

Post by 1970-01-01 »

krm01 wrote: post #546
1970-01-01 wrote: post #500

AI is really not "just software" anymore. It is able to discover facts and advance science. Hard to disagree that we're near or at the point where Artificial Intelligence has expanded reality into 4 quadrants: objects that are not alive: dust, rocks, water, wood, hats, lego, aluminum, etc. objects that are alive but not intelligent: trees, mold, staphylococcus, cancer, grapes, etc. objects that are alive and intellig…

SH is in the wrong bucket

Yes, sometimes I forget the obvious. Fixed with a different Steven.

Re: Claude Fable 5.1 and Claude Mythos 5.1

#620

Post by m101 »

I think the most interesting thing about this, that I can tell so far, is the cache hit discount. Anyone who had an autocompaction threshold optimised for their use case should consider upping it from where it is.

I would be interested in whether someone has done research here on these things as it seems a fairly complicated function to work out, and use case dependent. (?)

In some sense an expired kv cache is basically like an expensive cache hit, so your compaction token threshold should come in. Ideally claude code should allow you to vary the autocompaction threshold to vary with time since last token, but it doesn't of course. This perhaps suggests that someone should manage claude code through their own intermediary agent who manages these sorts of rules.

Lastly, I strongly suspect that anthropic isn't offering this price cut out of the kindness of their hearts. I am sure that they are to some extent banking on people not reacting to their price cut and leaving their autocompaction thresholds unchanged.

[edit - looks like the discount is only for the api, so they still don't give a rats ass about subs!]

Post reply on HN