I'll add another really positive review here. Sonnet 4.0 had been really struggling to implement an otel monitoring solution using grafana's lgtm stack. Sonnet 4.0 had 4 or 5 different attempts - some of them longer than 10 min - troubleshooting why metrics were supposedly being emitted from the api, but not showing up in Prometheus. Sonnet 4.5 correctly diagnosed and fixed the real issue within about 5 min. Not sure if that's the model being smarter, but I definitely saw the agent using some new approaches and seemingly managing it's context better.
Claude Sonnet 4.5
491–500 of 819 posts
Re: Claude Sonnet 4.5
#492Earlier quoted context omitted.
I think Codex working for 20 mins uninterrupted is actually a strength. It’s not “slow” as critics sometimes say - it’s thorough and autonomous. I can actually walk away and get something else done around the house while it does my work for me.
I swear cc in June/July used to spend a lot more time on tasks and felt more thorough like codex does now. Hard to remember much past the last week in this world though.
Yes I agree. I think Anthropic nerfed it considerably.
Re: Claude Sonnet 4.5
#493Earlier quoted context omitted.
That's a good call, I'll try to remember that for next time.
Have you thought about benchmarking models a month or two after release to see how it competes vs the day 1 release
For that to be useful I'd need to be running much better benchmarks - anything less than a few hundred numerically scored tasks would be unlikely to reliably identity differences.
An organization like Artificial Analysis would be a better fit for that kind of investigation: https://artificialanalysis.ai/
Re: Claude Sonnet 4.5
#494I had access to a preview over the weekend, I published some notes here: https://simonwillison.net/2025/Sep/29/claude-sonnet-4-5/ It's very good - I think probably a tiny bit better than GPT-5-Codex, based on vibes more than a comprehensive comparison (there are plenty of benchmarks out there that attempt to be more methodical than vibes). It particularly shines when you try it on https://claude.ai/ using its brand n…
Sorry I downvoted this by mistake. Got confused between collapse and the down arrow (which I rarely use). Does someone know how to reverse a downvote. I do not see it.
Re: Claude Sonnet 4.5
#495Earlier quoted context omitted.
I won’t be satisfied until I get a Linus Torvalds mode. “Your idea is shit because you are so fucking stupid” “Please stop talking, it hurts my GPUs thinking down to your level” “I may seem evil but at least I’m not incompetent”
I'm still holding out for _Marvin the depressed robot from Hitchhiker's Guide_ mode. "Why does anyone program anything?"
It's called Gemini
Re: Claude Sonnet 4.5
#496I had access to a preview over the weekend, I published some notes here: https://simonwillison.net/2025/Sep/29/claude-sonnet-4-5/ It's very good - I think probably a tiny bit better than GPT-5-Codex, based on vibes more than a comprehensive comparison (there are plenty of benchmarks out there that attempt to be more methodical than vibes). It particularly shines when you try it on https://claude.ai/ using its brand n…
Sorry I downvoted this by mistake. Got confused between collapse and the down arrow (which I rarely use). Does someone know how to reverse a downvote. I do not see it.
You should see an "unvote" or "undown" link to the right of the timestamp (i.e. the opposite side from where the vote arrows were). It's fairly subtle.
Re: Claude Sonnet 4.5
#497[deleted]
Re: Claude Sonnet 4.5
#498When I see how much the latest models are capable of it makes me feel depressed. As well as potentially ruining my career in the next few years, its turning all the minutiae and specifics of writing clean code, that I've worked hard to learn over the past years, into irrelivent details. All the specifics I thought were so important are just implementation details of the prompt. Maybe I've got a fairly backwards view…
That code taste of yours, your ability to understand the minutiae, makes you superhuman at managing agents. Comments, docstrings, naming, patterns - by defining better approaches and hold agents to them, the results will be better. Way better. You can't grow a meaningful codebase without solid underlying primitives. The entropy will eat you alive. Systems architecture is becoming more important - systems that play we…
Amen to all your points.
All senior devs know what a project looks like that had only juniors and no tech leadership. One big mess. Project stalls. Team spends 98% on bugs and emergencies, and still cant get a grip on curbing the drama. Why? All the point you say for AI are true for juniors as well: when to tell someone to redo a (part of) a project/feature? That same intuition works when collabbing with AI.
Re: Claude Sonnet 4.5
#499I just ran this through a simple change I’ve asked Sonnet 4 and Opus 4.1, and it fails too. It’s a simple substitution request where I provide a Lint error that suggests the correct change. All the models fail. I could ask someone with no development experience to do this change and they could. I worry everyone is chasing benchmarks to the detriment of general performance. Or the next token weight for the incorrect c…
That's what I was thinking too; the models have the same data sources (they have all scraped the internet, github, book repositories, etc), they all optimize for the same standardized tests. Other than marginally better scores in those tests (and they will cherry-pick them to make them look better), how do the various competitors differentiate from each other still? What's the USP?
LLM (the model) is not the agent (ClaudeCode) that uses LLMs.
LLMs improve slowly, but the agents are where the real value is produced: when should it write tests, when should it try to compile, how to move fwd from a compile error, can it click on your web app to test its own work, etc. etc.
Re: Claude Sonnet 4.5
#500When I see how much the latest models are capable of it makes me feel depressed. As well as potentially ruining my career in the next few years, its turning all the minutiae and specifics of writing clean code, that I've worked hard to learn over the past years, into irrelivent details. All the specifics I thought were so important are just implementation details of the prompt. Maybe I've got a fairly backwards view…
I used to think so. But now I think it's not very useful with what I've seen from others. Maybe if you do frontend.. The people who I see vibe coding with no experience actually programming... It is completely useless. It can only do the most simple tasks, anything beyond it will constantly make critical errors and random mistakes. That is using what was the latest Claude version before this. I've also not really used AI coding stuff myself at all do take that as you will.
Even for frontend tasks it makes mistakes when you ask too much of it...
What will it create for me? A basic react/nextjs frontend and a clone? Anything that requires more careful planning and esoteric functionality it can't do.
Oh yes, and the code I've seen it write... It can take what should be 20 lines of code and turn it into 600!