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GPT-5-Codex

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31–40 of 144 posts

Re: GPT-5-Codex

#31
Very impressive. I've been working on a shared background presence animation, and have been testing out Claude and Codex. (By shared presence, I mean imagine a page's background changing based on where everyone's cursor is)

Both were struggling yesterday, with Claude being a bit ahead. Their biggest problems came with being "creative" (their solutions were pretty "stock"), and they had trouble making the simulation.

Tried the same problem on Codex today. The design it came up with still felt a bit lackluster, but it did _a lot_ better on the simulation.

Re: GPT-5-Codex

#33
post #22

Earlier quoted context omitted.

So you're all saying suddenly codex cli w gpt 5 codex is better than claude code? Hard to believe

Not suddenly, it's been better since GPT-5 launched. Prompting is different, but in a good way. With Claude Code, you can use less prompting, and Claude will get token happy and expand on your request. Great for greenfield/vibing, bad for iterating on existing projects. With Codex CLI, GPT-5 seems to handle instructions much more precisely. It won't just go off on it's own and do a bunch of work, it will do what you…

Codex CLI of course will sometimes do the wrong thing, or sometimes do something extra that you didn't intend for it to do.

It seems about half my sessions quickly become "why did you do that? rip __ out and just do ___". Then again, most of the other sessions involve Codex correctly inferring what I wanted without having to be so specific.

Re: GPT-5-Codex

#34
The code review thing might be my favorite UX for AI based development. Largely stays out of your way and provides good comments.

I’m imagining if it can navigate the codebase and modify tests - like add new cases or break the tests by changing a few lines. This can actually verify if the tests were doing actual assertions and being useful.

Thorough reviewing like this probably benefits me the most - more than AI assisted development.

Re: GPT-5-Codex

#35
post #11
post #4

It's interest to see this quote: `for the bottom 10% of user turns sorted by model-generated tokens (including hidden reasoning and final output), GPT‑5-Codex uses 93.7% fewer tokens than GPT‑5` It sounds like it can make simple tasks much more correct. It's impressive to me. Today coding agent tends to pretend they're working hard by generating lots of unnecessary code. Hope it's true

This is my issue with gpt-5. If you use the low or medium reasoning it’s garbage. If you use high, it’ll think for up to five minutes on something dead simple.

Can you be more specific about what type of code you're talking about, and what makes it garbage?

I'm happy with medium reasoning. My projects have been in Go, Typescript, React Dockerfiles stuff like that. The code almost always works, it's usually not "Clean code" though.

Re: GPT-5-Codex

#36
From my observation of the past 2 weeks is that Claude Code is getting dramatically worse and super low usage quota's while OpenAI Codex is getting great and has a very generous usage quota in comparison.

For people that have not tried it in say ~1 month, give Codex CLI a try.

Re: GPT-5-Codex

#37
Doesn't seem ready for prime-time. I'll be impressed when it actually installs.

npm ERR! code 1 npm ERR! path /usr/local/lib/node_modules/@openai/codex/node_modules/@vscode/ripgrep npm ERR! command failed npm ERR! command sh -c node ./lib/postinstall.js npm ERR! /usr/local/lib/node_modules/@openai/codex/node_modules/@vscode/ripgrep/lib/download.js:199 npm ERR! zipFile?.close();

Re: GPT-5-Codex

#38
Oh since when Codex cli is now included as part of a ChatGPT plan? 99% sure that wasn't the case before. Time to try to use it for real.

Re: GPT-5-Codex

#39
post #22

Interesting, the new model's prompt is ~half the size (10KB vs. 23KB) of the previous prompt[0][1]. SWE-bench performance is similar to normal gpt-5, so it seems the main delta with `gpt-5-codex` is on code refactors (via internal refactor benchmark 33.9% -> 51.3%). As someone who recently used Codex CLI (`gpt-5-high`) to do a relatively large refactor (multiple internal libs to dedicated packages), I kept running in…

So you're all saying suddenly codex cli w gpt 5 codex is better than claude code? Hard to believe

It is 100% true. And they are rapidly losing users to Codex. Charts were shared recently showing a massive migration underway.

Re: GPT-5-Codex

#40
It's been interesting reading this thread and seeing that others have also switched to using Codex over Claude Code. I kept running into a huge issue with Claude Code creating mock implementations and general fakery when it was overwhelmed. I spent so much time tuning my input prompt just to keep it from making things worse that I eventually switched.

Granted, it's not an apples-to-apples comparison since Codex has the advantage of working in a fully scaffolded codebase where it only has to paint by numbers, but my overall experience has been significantly better since switching.

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