Comment by onomojo
3 hours ago
Any benchmark showing Opus 5 as the best just loses credibility for me. Anyone who's actually used Opus 5 daily knows what I'm talking about.
3 hours ago
Any benchmark showing Opus 5 as the best just loses credibility for me. Anyone who's actually used Opus 5 daily knows what I'm talking about.
Agreed, it's extremely frustrating. It's the only model that actually makes me curse when talking to it, even knowing how counterproductive it is.
Replying to myself, because I just bumped into these: https://www.reddit.com/r/claude/comments/1vfvdgz/anthropic_l... https://www.reddit.com/r/ClaudeAI/comments/1vgpyni/my_opus_5...
Especially the second one seems exactly like my experience.
The cursing thing blows my mind. "User is upset? Let's make decisions even faster (ie. more wrong) because clearly that's what they want!"
It's a simple switch to make: cursing = try harder instead of cursing = stop trying. Is it really impossible to train Claude that way?
I'd certainly rank it at the very top of the want to kill yourself when using it benchmark. It outperforms everything else on that leaderboard.
With weaker models you can sort of understand, they're trying their best and failing, but this thing just channels its immense inteligence into being as annoying as possible instead. I know it can do what I'm asking it to do, but it just finds a way to weasel out of it, or maybe just thinks for 10 minutes instead, then fixes one thing and breaks four additional ones.
yep matches my experience completely
But even fable has the annoying tendency to invent new jargon and produce an incomprehensible soup of text.
2 replies →
I'm dumbfounded to see Opus 5 making SO MANY mistakes in coding simple stuff. Most times, Fable 5 comes out to be cheaper because it nails so many things much quicker than Opus 5.
I have Fable plan and Opus implement. I haven't had any major issues working this way; however, Opus does seem plain fucking stupid compared to what I experienced with Sonnet previously.
I do the same, and generally have good results, but it does stupid things with gusto.
I'd open a blog with "weird things Opus did". Today it launched a swarm of cpu-hogging processes to test if the widget showing machine and I/O load is rendering nicely and correctly. The test went fine, but it was no longer able to kill those processes since they were really effectively hogging the CPU in various ways - being diligent, some of them were hogging CPU, some were murdering the SSD, some were pounding on the network adapters. Took me 30 mins to recover the machine to a working state without killing the meaningful, messy, in-flight sessions i had going on on other projects.
> however, Opus does seem plain fucking stupid
Infuriatingly so, in a way I don't remember Opus 4.8 being, but maybe I've just been ruined by Fable 5.
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Weird how different people's experiences are. If it's making simple mistakes something must be wrong in your setup/context I assume? It's been solid for me, beyond the usual LLMisms that all models have. But I keep context pretty minimal.
Every model that comes out comes with a bunch of people saying "this one is actually dumb they were smart before" and I don't really get it. The models since Opus 4.5 have all been basically the same to me. Sometimes they do the wrong thing, so you have to steer and stop and correct them. Leaving them to operate on their own in no-human-in-the-loop harnesses often gets bad results. But if you single thread it, and keep your work targeted (you have to know what you want the thing to do!), clear your context, the models will do what you ask pretty reliably.
Statements like this typically come from working on the same setup and context using different models. I actually have that very experience now; I work on something security-adjacent so Fable often drops out, at which point Opus behaves like its lobotomized half-sibling. Pardon me the language, but I can't find a better example to be honest.
Agreed. Opus 5 is doing just fine, slightly better than 4.8. It's personality is insufferable, but I find myself catching fewer problems at code review. It generally understands my conventions and isn't so eager to accrue tech debt.
> I'm dumbfounded to see Opus 5 making SO MANY mistakes in coding simple stuff.
To me it's not so much the dumb mistakes (although there are some of those) but the ultra-verbose, mega-inefficient "solutions" to some problems / prompts.
Stuff that "works" if you're the kind of person that considers slamming a semi-trailer at 200 mph into a door did, technically, result in the door being somehow "open".
As it's supposed to be one of the most advanced model, I can't help but wonder if the solutions are that bad/verbose/inefficient because we're already in a loop of models being trained on sloppy-pasta from previous models.
It works fine for me. Only issue I have is that it has me constantly reaching for the dictionary.
Sent to solve one task, came back with half of it solved and 2 more problems.
"One thing worth your attention", "Two things worth knowing", "One thing to eyeball"
And one of them is always something just completely out of scope and the other is something obvious it missed.
“One thing worth your attention, if you were to detonate a pipe bomb in your house, it would have a negative effect on your living room”.
This is driving me crazy. opus 4.8 did not do this to me not (at least during pre-5.0 timeframe). Feels like the new cycle is one step forward, two steps back.
Yeah, I've dropped back to 4.8 entirely for the remainder of this billing cycle. I'm going to be seriously looking into Qwen adoption and harness migration options over the course of August.
Same.
I could not get Opus 5 to do anything without losing a few years of my life from stress.
Fable has been okay but I am doing ML work and not allowed to use it which feels insane.
Ironically, Opus 5 is the most benchmaxxed model I've seen from Anthropic. It is legitimately smart in a lot of ways but it has communication issues, both in terms of how it communicates (all the autism of GPT class models, without the brevity) and how well it catches all the nuance of what you tell it.
It's my daily driver. I like it and find it noticeably better than Opus 4.8.
After I started reading complaints about Opus 5, I gave Fable the task of evaluating a bunch of code Opus 4.8 had written and compare it to Opus 5's code. Fable ran a dynamic workflow and the scores came back 15-20% higher for Opus 5's code in terms of quality, correctness and readability/conciseness. I did not tell Fable which Opus wrote which code, and I turned off memory as well to ensure there was no pollution from that angle.
My only complaint is that Opus 5's prose is annoying as hell. I wrote a custom skill for it for concise debriefs and it has been working pretty well for me.
What's the clear best, that you see?
Hilarious to see only different responses
GPT 5.6 Sol
GLM 5.2
Fable 5
It is infuriating to interact with, but it is also first in many blind test leaderboards on LLMArena
Can not confirm, for me it's the complete opposite.
I have some internal tests I use for areas where one particular solution/paradigm is dominant but worse.
Opus 4.6 is the last model that's actually useful and can "adjust" its perspective to use the newer & better solution.
Where Opus 4.8-5 has over fit training on worse/older but "dominant" solutions it refuses to adjust.
Not only does this create an existential threat to adopting progress but it also means that if you have a code base that has rare but real world tradeoff the newest versions of Opus 4.7, 4.8 and 5 are worse than useless and become a major dev timesink.
"As you requested, I've finished task X. Honestly, task X turned out to require task Y, which I haven't actually done. Task Y is the next step if you'd like to continue along this route."
Yeah, I told it to save in its memory that I don't want to have any more word salad!
This is the hard-won load-bearing quote.
Belt and braces all the way down
It's an infuriating model