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Two things LLM coding agents are still bad at

kix.dev

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Re: Two things LLM coding agents are still bad at

#111

Post by jeswin »

AllegedAlec wrote: post #99
jeswin wrote: post #68

Earlier quoted context omitted.

> I wanted it to refactor a parser in a small project This expression tree parser (typescript to sql query builder - https://tinqerjs.org/ ) has zero lines of hand-written code. It was made with Codex + Claude over two weeks (part-time on the side). Having worked on ORMs previously, it would have taken me 4x-10x the time to get to the same state (which also has 100s of tests, with some repetitions). That's a massive…

I have tried several. Overall I've now set on strict TDD (which it still seems to not do unless I explicitly tell it to even though I have it as a hard requirement in claude.md).

Claude forgets claude.md after a while, so you need to keep reminding. I find that codex does a design job better than Claude at the moment, but it's 3x slower which I don't mind.

Re: Two things LLM coding agents are still bad at

#112

Post by cimi_ »

rossant wrote: post #79
coldtea wrote: post #76

Earlier quoted context omitted.

> A few days later, just before deployment to production, I wanted to double check all 40 links. This was allowed to go to master without "git diff" after Codex was done?

It was a fairly big refactoring basically converting a working static HTML landing page into a Hugo website, splitting the HTML into multiple Hugo templates. I admit I was quite in a hurry and had to take shortcuts. I didn't have time to write automated tests and had to rely on manual tests for this single webpage. The diff was fairly big. It just didn't occur to me that the URLs would go through the LLMs and could b…

Speaking of agents and tests, here's a fun one I had the other day: while refactoring a large code base I told the agent to do something precise to a specific module, refactor with the new change, then ensure the tests are passing.

The test suite is slow and has many moving parts; the tests I asked it to run take ~5 minutes. The thing decided to kill the test run, then it made up another command it said was the 'tests' so when I looked at the agent console in the IDE everything seemed fine collapsed, i.e. 'Tests ran successfully'.

Obviously the code changes also had a subtle bug that I only saw when pushing its refactoring to CI (and more waiting). At least there were tests to catch the problem.

Re: Two things LLM coding agents are still bad at

#113

Post by jeswin »

pprotas wrote: post #109
iLoveOncall wrote: post #84

Earlier quoted context omitted.

Hum yeah, it shows. Just the fact that the API looks completely different for Postgre and SQLite tells us everything we need to know about the quality of the project here.

I guess the interesting question is whether @jeswin could have created this project at all if AI tools were not involved. And if yes, would the quality even be better?

Very true. However, to claim that the "API looks completely different for Postgre and SQLite" is disingenuous. What was he looking at?

Re: Two things LLM coding agents are still bad at

#114

Post by AllegedAlec »

coldtea wrote: post #80
AllegedAlec wrote: post #13

On a more important level, I found that they still do really badly at even a minorly complex task without extreme babysitting. I wanted it to refactor a parser in a small project (2.5K lines total) because it'd gotten a bit too interconnected. It made a plan, which looked reasonable, so I told it to do this in stages, with checkpoints. It said it'd done so. I asked it "so is the old architecture also removed?" "No, i…

> I feel like I have to tell it exactly to make changes X and Y to class Z, remove class A etc etc, at which point I can't let it do stuff unsupervised, which is half of the reason for letting an LLM do this in the first place. The reason better turn to "It can do stuff faster than I ever could if I give it step by step high level instructions" instead.

That would be a solution, yes. But currently it feels extremely borked from a UX perspective. It purports to be able to do this, but when you tell it to it breaks in unintuitive ways.

I hate this idea of "well you just need to understand all the arcane ways in which to properly use it to its proper effects".

It's like a car which has a gear shifter, but that's not fully functional yet, so instead you switch gear by spelling out in morse code the gear you want to go into using L as short and R as long. Furthermore, you shouldn't try to listen to 105-112 on the FM band on the radio, because those frequencies are used to control the brakes and ABS and if you listen to those frequencies the brakes no longer work.

We would rightfully stone any engineer who'd design this and then say "well obvious user error" when the user rightfully complains that they crash whenever they listen to Arrow FM.

Re: Two things LLM coding agents are still bad at

#115

Post by hansmayer »

ivape wrote: post #90
hansmayer wrote: post #89

Earlier quoted context omitted.

Yeah so, the reason people use various tools and machines in the first place is to simplify the work or everydays tasks by : 1) Making the tasks execute faster 2) Getting more reliable outputs then doing this by yourself 3) Making it repeatable . The LLMs obviously dont check any of these boxes so why don´t we stop pretending that we as users are stupid and don´t know how to use them and start taking them for what th…

[flagged]

Stop what mate? My words are not the words of someone who ocassionally dabbles in the free ChatGPT layer - I've been paying premium tier AI tools for my entire company for a long time now. Recently we had to scale back their usage to just consulting mode, i.e. because the agent mode has gone from somewhat-useful to complete waste of time. We are now back to using them as replacement for the now entshittified search. But as you can see by my early adopting of these crap-tools, I am open-minded. I'd love to see what great new application you have built using them. But if you don't have anything to show, I'll also take some arguments, you know, like the stuff I provided in my first comment.

Re: Two things LLM coding agents are still bad at

#116

Post by amelius »

rossant wrote: post #37

Recently, I asked Codex CLI to refactor some HTML files. It didn't literally copy and pasted snippets here and there as I would have done myself, it rewrote them from memory, removing comments in the process. There was a section with 40 successive links with complex URLs. A few days later, just before deployment to production, I wanted to double check all 40 links. First one worked. Second one worked. Third one worke…

In these cases I explicitly tell the llm to make as few changes as possible and I also run a diff. And then I reiterate with a new prompt if too many things changed.

Re: Two things LLM coding agents are still bad at

#117

Post by amelius »

I recently asked an llm to fix an Ethernet connection while I was logged into the machine through another. Of course, I explicitly told the llm to not break that connection. But, as you can guess, in the process it did break the connection.

If an llm can't do sys admin stuff reliably, why do we think it can write quality code?

Re: Two things LLM coding agents are still bad at

#118

Post by freetonik »

NitpickLawyer wrote: post #92
freetonik wrote: post #86

Earlier quoted context omitted.

Ok, not trivial for sure, but not novel? IIUC, the language does not have really new concepts, apart from the keywords (which is trivial). Impressive nonetheless.

Novel as in never done before? Of course not. Novel as in "an LLM can maintain coherence on a 100k+ LoC project written in zig"? Yeah, that's absolutely novel in this space. This wasn't possible 1 year ago. And this was fantasy 2.5 years ago when chatgpt launched. Also impressive in that cc "drove" this from a simple prompt. Also impressive that cc can do stuff in this 1M+ (lots of js in the extensions folders?) repo…

>Novel as in "an LLM can maintain coherence on a 100k+ LoC project written in zig"? Yeah, that's absolutely novel in this space.

Absolutely. I do not underestimate this.

Re: Two things LLM coding agents are still bad at

#119

Post by dude250711 »

hshdhdhehd wrote: post #72
rossant wrote: post #37

Recently, I asked Codex CLI to refactor some HTML files. It didn't literally copy and pasted snippets here and there as I would have done myself, it rewrote them from memory, removing comments in the process. There was a section with 40 successive links with complex URLs. A few days later, just before deployment to production, I wanted to double check all 40 links. First one worked. Second one worked. Third one worke…

Well using an LLM is like rolling dice. Logits are probabilities. It is a bullshit machine.

Yeah, it read like "when running with scissors be careful out there". How about not running with scissors at all?

Unless of course the management says "from now on you will be running with scissors and your performance will increase as a result".

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