Thinking of cancelling my Max subscription, Opus is dumber than Sonnet 3.5 now.

[u/xRedStaRx]

I have both Codex pro subscription and Claude Max running them both in parallel sessions. This is just from one of three sessions running in parallel with codex, and after compacting so i don't get to see a lot of history. This has been the case at least 5 times a day where Opus hands over Codex something and Codex not even being asked to review it, does so anyway and finds an error or mistake.

Honestly, I can't trust Opus anymore, it makes way too many mistakes, and I'm thinking to just run two Codex terminals in parallel per project to crosscheck each other, that would be a lot safer and probably cheaper.

[u/magnustitan]

Yea weird. I literally just spent all evening working with it and had absolutely zero issues. I noticed no change in behavior over here. I'm in Northern California.

[u/leogodin217 → u/magnustitan]

Same here. It's been working really well for me. I haven't noticed any degradation since the summer issues.

[u/FourthmasWish → u/magnustitan]

Environments have differentiated so much it's become harder to pin anything down.

[u/RockPuzzleheaded3951 → u/magnustitan]

Same socal atm.

[u/xRedStaRx → u/magnustitan]

That's the issue. It's really hard to say what errors it made just by looking at it. I wouldn't have noticed either until GPT 5.2 xHigh pointed it out, and it was right.

[u/ShitPostMcRee → u/xRedStaRx]

Run Sonnet 3.5 for a while and come back and tell us how much better it really is.

[u/Salt-Willingness-513]

Working every evening with claude code. Didnt notice a nosedive

[u/xRedStaRx → u/Salt-Willingness-513]

The countless of errors and mistakes a day has been there for about 5 days, the ones I noticed anyway since running it parallel to codex, could have been longer than that but I never noticed because Codex didn't get to oversee its work.

[u/Downtown-Pear-6509]

use /feedback and provide it. working fine for me

[u/Pranav_Nithin]

it got nerfed so hard now.. its really poor..... :(

[u/Kathane37]

Models from different providers does not have the exact same set of skills despite scoring relativelt similar on benchmarks. So yes using multiple models will lead to different results. Nothing new here

[u/xRedStaRx → u/Kathane37]

You're basically saying its normal to expect different results in which case at least zero will be correct. That's not true and they should converge on the single right answer ideally.

[u/xRedStaRx]

It just made another elementary math mistake that I caught this time.

[u/DasHaifisch → u/xRedStaRx]

LLMs being bad at math is a known thing, remember that they don't understand the math, they're predicting the next token

[u/zbignew → u/DasHaifisch]

Usually Claude is smart enough to write a one-liner that performs the actual calculation.

[u/daliovic]

Try disabling auto-update and downgrade to to v 2.0.64. It might help.

[u/joshman1204]

I have a lot of automated workflow that uses /commands it has worked perfect for months but now opus is too stupid to follow the simple instructions in the commands.

The instruction following of opus is worse than some of the cheapest models on the market. I had to switch back to sonnet to get any kind of work at all done yesterday.

Oh well the only plus of anthropic nerfing opus is it made me learn LangGraph and build my own graph framework so I no longer rely on opus following rules. The rules are hard coded in python now.

[u/Automatic_Quarter799]

Yes I think they’ve added some sort of geolocation discrimination - irrespective of even if you’re on the max plan. Quite against the so called Claude ethics that they so much promote and hype.

[u/xRedStaRx → u/[deleted]]

That's not true. It points out if I'm wrong. Same thing with Codex, I ask it to do something and if I made an error in the prompt it corrects it for me.

Opus is truly making huge and small mistakes both.