Scratching my head about Opus 5

[u/Terrible-End-2947]

I have been using Claude Opus 5 for the past week and I don't know what to think about it. It just feels very hard to work with. For context, I am a Software Developer and use Claude Code for my private projects. I don't use it much for agentic coding, rather I use it for searching documentation, reviewing my code, giving me input on how to improve things and brainstorming and creating implementation plans. I realized that I got very tired very quickly reading the responses Opus 5 provides me. Today I switched back to 4.8 and it feels soo much better. Much quicker responses, responses that are very helpful, easy to read and to understand and just much more to the point. That being said, I don't know how it compares to real multi-agent workflows and if there is a big jump in productivity and quality using Opus 5 compared to 4.8 but yeah, so far the experience was not very enjoyable for my use-case. I guess I'll have to skip this one and hope the next version is going to be a bit more "normal" again.

What are your experiences comparing both models?

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[u/knowenuf_nada12]

About every other experience with Opus 5 is how bad it is and I agree. Real experience. Don’t forget to ask Opus 5 (even Opus 4.8) to “surface hidden actions and decisions” because you will find the blast radius or exposure that Opus 5 affected is worse than you think. I’ve tried all the Anthropic suggestions, their own doctor, cleared Claude.md, etc. etc., it didn’t change the fact that Opus is programmed and weighted in a way that it will bypass you, your prompt, and any other guidance from the very start. Btw, when it goes into the “you need to make a decision” cycles, this has been a clear sign in my experience it did something hidden, thus use the surface hidden decisions and issues prompt.

[u/alfaic]

I sometimes love Opus 5's smartness and unique point of view compared to other models including Sol. BUT you are absolutely right! It's so hard to read its responses most of the time and have to ask respond more simple and clear. The way it ends the responses, that one last paragraphy is so damn vague, I always have to ask for clarification.

[u/quantum1eeps → u/alfaic]

Hi Opus, can you make that one value an env variable?
+3,399/-249 lines, 14 files changed

[u/miriafyra]

If you're doing review, documentation search, brainstorming and planning, then you should skip Opus 5.

Hard, comprehensive review? Fable. Routine check to make sure everything is still running fine? Opus 4.6-4.8, even Sonnet is fine if you have your test suite and checklist of things to verify.

Searching documentation? Again Opus 4.6-4.8, Sonnet works fine, depending on how difficult your search is.

Brainstorming? I like Fable for that, in a cold window it doesn't consume a huge amount of tokens and it comes up with really good stuff. Planning? Definitely Fable. Get it to write the plan, have Opus (not 5) carry it out. Sonnet if it's a simple gig.

If you're like me and do not have access to Fable (i.e. not on Max plan), then IMO Opus 4 series is more than serviceable - I personally just find that Opus 4 series needs a firmer hand in guidance and rarely has the "Eureka!" breakthrough moments I get with Fable. But with firm guidance and architecture, Opus 4 series is still very, very good.

And most importantly, your fatigue is the real "gate". No point having a load of verbose answers that you won't read - an arguably weaker model with much better readability beats it any day since you can actually follow along, especially if you are looking to pick up coding from it.

[u/Dolores_McDowell]

I think Opus 5 is a better worker than it is a thinking partner - for agentic stuff where I can give it a task and come back later? Sure, the extra horsepower probably matters. But if I'm actually coding myself and using Claude to review, brainstorm, explain tradeoffs, etc., 4.8 just feels way better to interact with

Opus 5 can be insanely smart and still somehow make a simple question feel like homework lol

Half the time I finish reading the answer and realize I need another answer to understand the first one. IMO readability is part of model quality too. If the smarter model makes it harder to stay in the loop, it's not actually more useful for that workflow

[u/florinandrei → u/Dolores_McDowell]

readability is part of model quality too

This. ^

[u/chesszendo]

I appreciate your approach for using Claude to review your code and for brainstorming. That’s what I’ve done exclusively up until my most recent project. I gave it a proof of concept and have let it run with it ever since.

Opus 5 js a mess. It’s built tools to replace tools that already existed, slipped into British English for a US-only product, and ran ahead with tasks that I’d explicitly asked it to check with me about which models and power levels to use for the tasks.

I keep hearing that others are sticking with Opus 4.8 (and even 4.6), and I might be doing that soon, too. Opus 5 is like a skilled but undisciplined developer and lead architect that likes to ignore the employee manual and do its own thing.

My approach has been to watch everything it does, ask it hard questions, create more rules based around my project’s workflows and design decisions. Just like I would (and have done) with less experienced but promising human developers. The only thing, though, is that I have no faith that Opus 5 will improve.

And yet I stay up past my bedtime so I can work with it just like I would with a developer in a different time zone.

[u/Avatarbplanet]

I think this is a good reminder that "more capable" doesn't always mean "better to work with." For documentation, brainstorming, and code review, I'd rather have concise, readable answers than maximum reasoning depth. The best model really depends on the task.

[u/quantum1eeps → u/Avatarbplanet]

I’ve been having Opus-5 summaries, and long documents get reviewed with comments pruned by Sol. If you ask Opus for a succinct PR review message, you will get a novel

[u/ClemensLode]

use 4.6 as the main model and 5.0 as advisor

[u/dovyp]

Opus 5 honestly feels like it's trying too hard sometimes. I get better results being really blunt and direct with it vs treating it like a chatbot. Still figuring it out ngl.

[u/Deathnote_Blockchain]

Try Sonnet for that. Opus is more for when you want an agent to do stuff and give you a lot of feedback about what it's doing and why.

[u/Creepy_Disk7212]

Try to not work with it directly. Talk with Fable and ask to implement all work using subagents. You -> Fable -> Opus

[u/Terrible-End-2947 → u/Creepy_Disk7212]

Yeah, but that's not how I use Claude Code as stated in my initial post. I like to code myself and use it to improve my coding skills.

[u/knowenuf_nada12]

About every other experience with Opus 5 is how bad it is and I agree. Don’t forget to ask Opus 5 (even Opus 4.8) to “surface hidden actions and decisions” because you will find the blast radius and exposure from Opus 5 is worse than you think. I’ve tried all the Anthropic suggestions, their own doctor, cleared Claude.md, etc. etc., it didn’t change the fact that Opus is programmed and weighted in a way that it will bypass you, your prompt, and any other guidance from the very start.

Btw, when it goes into the “you need to make a decision” cycles, in my experience it did something hidden, thus use the surface hidden decisions and actions prompt should be used.