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Two things LLM coding agents are still bad at

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Re: Two things LLM coding agents are still bad at

#121

Post by globular-toast »

amelius wrote: post #116
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.

You can always run a diff. But how good are people at reading diffs? Not very. It's the kind of thing you would probably want a computer to do. But now we've got the computer generating the diffs (which it's bad at) and humans verifying them (which they're also bad at).

Re: Two things LLM coding agents are still bad at

#122

Post by petesergeant »

aragonite wrote: post #70

Has anyone had success getting a coding agent to use an IDE's built-in refactoring tools via MCP especially for things like project-wide rename? Last time I looked into this the agents I tried just did regex find/replace across the repo, which feels both error-prone and wasteful of tokens. I haven't revisited recently so I'm curious what's possible now.

That's interesting, and I haven't, but as long as the IDE has an API for the refactoring action, giving an agent access to it as a tool should be pretty straightforward. Great idea.

Re: Two things LLM coding agents are still bad at

#123

Post by lenkite »

worldsayshi wrote: post #69
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…

This is of course bad but: humans also makes (different) mistakes all the time. We could account for the risk of mistakes being introduced and make more tools that validate things for us. In a way LLM:s encourage us to do this by adding other vectors of chaos into our work. Like, why not have tools built into our environment that checks that links are not broken? With the right architecture we could have validations…

In the above kind of described situation, a meticulous coder actually makes no mistakes. They will however make a LOT more mistakes if they use LLM's to do the same.

I have already had to correct a LOT of crap similar to the above in refactoring-done-via-LLM over the last year.

When stuff like this was done by a plain, slow, organic human, it was far more accurate. And many times, completely accurate with no defects. Simply because many developers pay close attention when they are forced to do the manual labour themselves.

Sure the refactoring commit is produced faster with LLM assistance, but repeatedly reviewing code and pointing out weird defects is very stressful.

Re: Two things LLM coding agents are still bad at

#124

Post by Xss3 »

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…

This is a horror story about bad quality control practices, not the use of LLMs.

Re: Two things LLM coding agents are still bad at

#125

Post by coldtea »

AllegedAlec wrote: post #114
coldtea wrote: post #80

Earlier quoted context omitted.

> 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 s…

>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.

Thankfully as programmers we know better and don't need to care what the UI pretends to be able to do :)

>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.

We might curse the company and engineer who did it, but we would still use that car and do those workarounds, if doing so allowed us to get to our destination in 1/10 the regular time...

Re: Two things LLM coding agents are still bad at

#127

Post by olejorgenb »

aragonite wrote: post #70

Has anyone had success getting a coding agent to use an IDE's built-in refactoring tools via MCP especially for things like project-wide rename? Last time I looked into this the agents I tried just did regex find/replace across the repo, which feels both error-prone and wasteful of tokens. I haven't revisited recently so I'm curious what's possible now.

Serena MCP does this approach IIRC

Re: Two things LLM coding agents are still bad at

#128

Post by ogogmad »

sebtron wrote: post #91
ivape wrote: post #65

Earlier quoted context omitted.

Well, you see it hallucinates on long precise strings, but if we ignore that, and focus on what it’s powerful at, we can do something powerful. In this case, by the time it gets to outputting the url, it already determined the correct intent or next action (print out a url). You use this intent to do a tool call to generate a url. Small aside, it’s ability to figure what and why is pure magic, for those still peddlin…

> Well, you see it hallucinates on long precise strings But all code is "long precise strings".

He obviously means random unstructured strings, which code is usually not.

Re: Two things LLM coding agents are still bad at

#130

Post by mr_mitm »

lenkite wrote: post #123
worldsayshi wrote: post #69

Earlier quoted context omitted.

This is of course bad but: humans also makes (different) mistakes all the time. We could account for the risk of mistakes being introduced and make more tools that validate things for us. In a way LLM:s encourage us to do this by adding other vectors of chaos into our work. Like, why not have tools built into our environment that checks that links are not broken? With the right architecture we could have validations…

In the above kind of described situation, a meticulous coder actually makes no mistakes. They will however make a LOT more mistakes if they use LLM's to do the same. I have already had to correct a LOT of crap similar to the above in refactoring-done-via-LLM over the last year. When stuff like this was done by a plain, slow, organic human, it was far more accurate. And many times, completely accurate with no defects.…

A meticulous coder probably wouldn't have typed out 40 URLs just because they want to move them from one file to another. They would copy-past them and run some sed-like commands. You could instruct an LLM agent to do something similar. For modifying a lot of files or a lot of lines, I instruct them to write a script that does what I need instead of telling them to do it themselves.
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