No idea why his shit keeps getting submitted.

I mean, I really, really see intelligence tank at a certain amount of context usage. I always start a new session when any implementation work is starting or when starting a new plan.

So I clean context before writing a plan, I clean context before any implementation of a plan. My first prompt is always putting enough of my own context, copy and pastes of docs, etc, to ensure the plan creation is good. Once the plan is made I clean the context and get Opus to implement said plan.

Out of all the methodologies I've tried, this seems to be the best in terms of output quality.

And yes, the parent poster is accurate, Fable is just as prone to moronic mistakes as Opus was. Stop being so AI-pilled.

Codex is still a better model, and yes, for the hardest engineering problems. I use Claude for UI/GUIs and Codex for all my backend, because I have 20 years of experience of actual hard engineering, and I can see that Codex writes, cleaner code, and is far more steerable.

Bad engineers think Claude is better because it writes more lines of code and is more "proactive", but lines of code doesn't make a better system.

I've used Claude Code and Codex since release and use them both in parallel. Codex is still better (yes even with Fable).

Claude Code is best for UI, nice looking guis, etc, and apparently also best at impressing mediocre programmers who are prone to AI psychosis.

All the best engineers I worked with in past jobs (faang folk, spacex, x.ai, and others) all use Codex, go figure.

For me, Claude makes bone headed decisions all the time, like glaring errors, not even particularly subtle.

But the more obvious flag is the amount of irrelevant code and tests which Fable writes. Like it regularly writes 2X or 3X the amount of code and tests that are needed. It’s an expert at writing plausible but entirely useless tests.

But I think that if you’re a more junior engineer or haven’t been around a the block you can easily think that “more code equals smarter”. Claude ends up creating a massive, hard to manage codebase, and if you look the Claude Code codebase (which was leaked), you can see I’m right!

The Claude Code codebase is terrible. And presumably Anthropic has been using their smartest models for working on Claude Code. I wrote my own coding harness with Codex (as a fun experiment) which used a fraction of the code and is about 100X more performant and memory efficient (than Claude Code)!

The only thing I have Fable do now is create UIs or otherwise front-ends for systems where correctness doesn't matter as much.

Anthropic models lead at making nice looking UIs for sure, but when it comes to making sure my Rust code is actually 100% correct and uses 1% of CPU most of the time, Codex is king.

Note, this is better than it was with Opus, where it was more like 90% of the time the Codex plans were obviously better.

As in, I give the exact same prompt to Fable and GPT 5.5 Pro, then produce the plans, then give each model the other's plan. Claude always realizes it missed stuff and Codex usually ends up finding missing things in Claudes plan.

This situation did improve with Fable versus Opus 4.8, but in general, Codex for me is still the better model.

Claude still (and has always) writes far too much code to fulfill a given spec or plan. It misses edge cases and is generally far too verbose.

Claude also is (and even more so with Fable) super tokenmaxxing, i.e. it seems tuned to use the max amount of tokens per task, whereas Codex will simply get your job done as you specified with the minimum fuss and tokens.

Codex feels way more steerable and just more "professional" as though I'm working with a seasoned engineer, versus someone smart but over excitable, like a super smart associate engineer.

That doesn't make it smart or aggressive, if anything it's just been turned to crank tokens until something happens, which doesn't make it a good model.

Why are you positively anthropomorphizing this? It's an LLM, it's been tuned via RL, and it's been tuned by engineers at Anthropic to use a metric fuck-load of sub-agents and tokens to presumably pump their pre-IPO revenue!

A co-worker managed to get Fable to spin up 50 (!!!) sub-agents for a problem which codex worked on with 3 sub-agents. What the hell is going on here? It certainly doesn't mean Fable is "smarter" than Codex.

I've tested it extensively and I'm still using GPT 5.5 High Fast as my primary engineering model. It's far more steerable, writes less, higher quality code, and consistently finds issues and edge cases which are not found by Fable or Opus 4.7.

I use both and the only thing (as always) that I will use Claude for is UI design.

Opus 4.8 and now Fable are still both worse at actually getting the job done than the Codex model. Claude models write FAR too much code when it's not needed, they burn far too many tokens, when they are not needed, write un-necessary tests, write plans which are 5 pages longer than are needed, etc. etc.

Have you actually compared code quality and plan quality versus Codex? It's demonstrably worse.

I mean, we have a lot of weird shit going down right now... like AI being used to automate art BEFORE it's being used to automate dangerous and menial jobs, but knowing that people are being killed with help from data generated by millions of kids and young adults playing a fun, cute videogame is just so freaking dark and weird.

We are a very strange species and I don't have a great deal of hope for our future.