Claude Opus 4.8 • Hacker News Board

Re: Claude Opus 4.8

#631

Post by nikcub » Thu, May 28, 2026, 10:13 PM UTC

gigatexal wrote: post #425

NiloCK wrote: post #77

A rambling comment: I think this is the first time we've had a third minor version bump on a frontier Anthropic model. (I count the 0.5s as major here, because they've been issued non-sequentially and also corresponded to massive capability leaps, eg, Sonnet 3.5, Opus 4.5). So now the Opus 4.5 family has successors 4.6, 4.7, and 4.8, each posting fairly modest claimed gains. My own experience w/ 4.6 and 4.7 are that…

why are the models the same price? https://platform.claude.com/docs/en/about-claude/pricing ``` Model Base Input Tokens 5m Cache Writes 1h Cache Writes Cache Hits & Refreshes Output Tokens Claude Opus 4.8 $5 / MTok $6.25 / MTok $10 / MTok $0.50 / MTok $25 / MTok Claude Opus 4.7 $5 / MTok $6.25 / MTok $10 / MTok $0.50 / MTok $25 / MTok Claude Opus 4.6 $5 / MTok $6.25 / MTok $10 / MTok $0.50 / MTok $25 / MTok Claude Op…

Same price on a token basis, but usually steadily decreasing on a task basis

Re: Claude Opus 4.8

#632

Post by whereistejas » Thu, May 28, 2026, 10:14 PM UTC

This may be the most important sentence in that announcement:

> expect to be able to bring Mythos-class models to all our customers in the coming weeks.

Re: Claude Opus 4.8

#633

Post by throwatdem12311 » Thu, May 28, 2026, 10:17 PM UTC

merlindru wrote: post #138

gAI wrote: post #115

Earlier quoted context omitted.

4.7 was the first time I had to resort to using the previous version (4.6) for most use cases. Hoping 4.8 rectifies this.

Same. 4.7 felt like a definite regression

4.7 was just them starting on the path on getting prices in line with the actual cost

Make it dumber. Charge more (by changing the tokenizer). Call it the latest and greatest. Reset expectations.

Re: Claude Opus 4.8

#634

Post by pheller » Thu, May 28, 2026, 10:17 PM UTC

IFC_LLC wrote: post #309

Ugh... Invalid request The request couldn't be completed. View details API Error: 400 messages.1.content.7: `thinking` or `redacted_thinking` blocks in the latest assistant message cannot be modified. These blocks must remain as they were in the original response. I would rather not. 4.6 was fine. 4.7 got to be fine 1 week after the release. Now 4.8. No difference, same thing. But the app is broken and nothing works.…

I'm getting this near constantly even after toggling to a different model and compacting. Ugh indeed.

Re: Claude Opus 4.8

#635

Post by mrinterweb » Thu, May 28, 2026, 10:17 PM UTC

NiloCK wrote: post #77

A rambling comment: I think this is the first time we've had a third minor version bump on a frontier Anthropic model. (I count the 0.5s as major here, because they've been issued non-sequentially and also corresponded to massive capability leaps, eg, Sonnet 3.5, Opus 4.5). So now the Opus 4.5 family has successors 4.6, 4.7, and 4.8, each posting fairly modest claimed gains. My own experience w/ 4.6 and 4.7 are that…

The more difficult it is for humans to consistently and accurately compare model outputs the more opportunity there is to spread FUD (Fear, Uncertainty, Doubt). Considering valuations of these companies and the astronomical investments being made, a sabotage campaign with bots or paid users on reddit, twitter, YouTube, or whatever socials could go a long way towards knocking market cap off the competition. Not saying that's happening, just saying its an obvious target. Even if the goal is not nefarious, people with a perceived bad experience are 2-3x more likely to complain. So even without bad actors involved, a new model may need to be significantly better in order to break even on the old net promoter score.

Re: Claude Opus 4.8

#636

Post by swalsh » Thu, May 28, 2026, 10:17 PM UTC

scuderiaseb wrote: post #541

northern-lights wrote: post #23

> Not only that, but we plan to release a new class of model with even higher intelligence than Opus. As part of Project Glasswing, a small number of organizations are currently using Claude Mythos Preview for cybersecurity work. Models of this capability level require stronger cyber safeguards before they can be generally released. We’re making swift progress on developing these safeguards and expect to be able to b…

So this is how they’ll remove access from Claude Pro to the biggest models. You would need at least a Claude Max subscription for the bigger than Opus models I bet.

Its amazing how quickly ive just become accustomed to being a max subscriber. I dont think I could go back to pro.

Re: Claude Opus 4.8

#637

Post by defgeneric » Thu, May 28, 2026, 10:17 PM UTC

silverlight wrote: post #236

Unfortunately they seem to have straight up broken Claude Code either with this release in the backend or the new CC version. Errors about "can't modify thinking blocks" are bricking long-running sessions: https://github.com/anthropics/claude-code/issues?q=is%3Aissu...

In case it helps anyone, in some minor cases I was able to recover and continue with /rewind.

Re: Claude Opus 4.8

#638

Post by giwook » Thu, May 28, 2026, 10:17 PM UTC

The way that Mythos is likely being used to train these publicly available models, I wonder if there will always be a private, mostly/wholly internal model that is significantly ahead technically but is reserved for internal or "VIP" use.

Re: Claude Opus 4.8

#639

Post by ismailmaj » Thu, May 28, 2026, 10:19 PM UTC

I just asked the model details about the incoming spaceX IPO and it responded with “There’s no confirmed SpaceX IPO. Elon Musk has said for years that SpaceX itself won’t go public”. It took me two push backs and specifically asking for web search.

I feel like I won’t like this model just like I didn’t like 4.7, push backs a lot and avoids thinking or search as much as possible.

Re: Claude Opus 4.8

#640

Post by zamalek » Thu, May 28, 2026, 10:19 PM UTC

northern-lights wrote: post #23

> Not only that, but we plan to release a new class of model with even higher intelligence than Opus. As part of Project Glasswing, a small number of organizations are currently using Claude Mythos Preview for cybersecurity work. Models of this capability level require stronger cyber safeguards before they can be generally released. We’re making swift progress on developing these safeguards and expect to be able to b…

> Probably more interesting

It is widely suspected that self-inflicted "bad news" ("Mythos is so dangerous we just can't give the public access to it") is nothing more than Dario's typical style of marketing - keep in mind that they have an IPO coming up, because he certainly factors that into everything he says in public (as is his responsibility, to be fair).

An alternative reason for delaying the model might not be "we are trying to make it safe." It could be "we don't know how to host this thing at scale, or cost-effectively".

GPT 5.5 has already been shown to be as adept as Mythos at finding vulnerabilities.

Finally, laymen massively underestimate the importance of the harness for model performance. OpenHands existed long before Claude Code, Claude Code changed everything because of the clever hand-holding it does. Mythos is definitely more than just a model.