Live data from Hacker News

Are LLM merge rates not getting better?

entropicthoughts.com

61–70 of 175 posts

Re: Are LLM merge rates not getting better?

#61
I feel that two things are true at the same time:

1) Something happened during 2025 that made the models (or crucially, the wrapping terminal-based apps like Claude Code or Codex) much better. I only type in the terminal anymore.

2) The quality of the code is still quite often terrible. Quadruple-nested control flow abounds. Software architecture in rather small scopes is unsound. People say AI is “good at front end” but I see the worst kind of atrocities there (a few days ago Codex 5.3 tried to inject a massive HTML element with a CSS before hack, rather than proprerly refactoring markup)

Two forces feel true simultaneously but in permanent tension. I still cannot make out my mind and see the synthesis in the dialectic, where this is truly going, if we’re meaningfully moving forward or mostly moving in circles.

Re: Are LLM merge rates not getting better?

#62
I think what happened with static image generation is happening with LLMs. Basically the tools around are becoming better, but all the AI improvements stall, the error rate stay the same (but external tools curate the results so it won't be noticeable if you don't run your own model), the accuracy is still slightly improving, but slower and slower, and never reach the 'perfect' point. Basically stablediffusion early 2025

Re: Are LLM merge rates not getting better?

#63

I don't find this very compelling. If you look at the actual graph they are referencing but never showing [1] there is a clear improvement from Sonnet 3.7 -> Opus 4.0 -> Sonnet 4.5. This is just hidden in their graph because they are only looking at the number of PRs that are mergable with no human feedback whatsoever (a high standard even for humans). And even if we were to agree that that's a reasonable standard, G…

I don't know that graph to me shows Sonnet 4.5 as worse than 3.7. Maybe the automated grader is finding code breakages in 3.7 and not breaking that out? But I'd much prefer to add code that is a different style to my codebase than code that breaks other code. But even ignoring that the pass rate is almost identical between the two models.

Re: Are LLM merge rates not getting better?

#64
LLM's have 100% gotten better, but it's hard to say if it's "intrinsically better", if that makes sense.

> OpenAI’s leading researchers have not completed a successful full-scale pre-training run that was broadly deployed for a new frontier model since GPT-4o in May 2024 [1]

That's evidence against "intrinsically better". They've also trained on the entire internet - we only have 1 internet, so.

However, late 2024 was the introduction of o1 and early 2025 was Deepseek R1 and o3. These were definitely significant reasoning models - the introduction of test time compute and significant RL pipelines were here.

Mid 2025 was when they really started getting integrated with tool calling.

Late 2025 is when they really started to become agentic and integrate with the CLI pretty well (at least for me). For example, codex would at least try and run some smoke tests for itself to test its code.

In early 2026, the trend now appears to be harness engineering - as opposed to "context engineering" in 2025, where we had to preciously babysit 1 model's context, we make it both easier to rebuild context (classic CS trick btw: rebooting is easier than restoring stale state [2]) and really lean into raw cli tool calling, subagents, etc.

[1] https://newsletter.semianalysis.com/p/tpuv7-google-takes-a-s...

[2] https://en.wikipedia.org/wiki/Kernel_panic

FWIW, AI programming has still been as frustrating as it was when it was just TTC in 2025. Maybe because I don't have the "full harness" but it still has programming styles embedded such as silent fallback values, overly defensive programming, etc. which are obvoiusly gleaned from the desire to just pass all tests, rather than truly good programming design. I've been able to do more, but I have to review more slop... also the agents are really unpleasant to work with, if you're trying to have any reasonable conversation with them and not just delegate to them. It's as if they think the entire world revolves around them, and all information from the operator is BS, if you try and open a proper 2-way channel.

It seems like 2026 will go full zoom with AI tooling because the goal is to replace devs, but hopefully AI agents become actually nice to work with. Not sycophantic, but not passively aggressively arrogant either.

Re: Are LLM merge rates not getting better?

#65

I feel that two things are true at the same time: 1) Something happened during 2025 that made the models (or crucially, the wrapping terminal-based apps like Claude Code or Codex) much better. I only type in the terminal anymore. 2) The quality of the code is still quite often terrible. Quadruple-nested control flow abounds. Software architecture in rather small scopes is unsound. People say AI is “good at front end”…

> People say AI is “good at front end”

I only say that because I'm a shit frontend dev. Honestly, I'm not that bad anymore, but I'm still shit, and the AI will probably generate better code than I will.

Re: Are LLM merge rates not getting better?

#66

Anecdotally, I haven't seen any real improvement from the AI tools I leverage. They're all good-ish at what they do, but all still lie occasionally, and all need babysitting. I also wonder how much of the jump in early 2025 comes from cultural acceptance by devs, rather than an improvement in the tools themselves.

[deleted]

Re: Are LLM merge rates not getting better?

#67
From the METR study (https://metr.org/notes/2026-03-10-many-swe-bench-passing-prs...):

>To study how agent success on benchmark tasks relates to real-world usefulness, we had 4 active maintainers from 3 SWE-bench Verified repositories review 296 AI-generated pull requests (PRs). We had maintainers (hypothetically) accept or request changes for patches as well as provide the core reason they were requesting changes: core functionality failure, patch breaks other code or code quality issues.

I would also advise taking a look at the rejection reasons for the PRs. For example, Figure 5 shows two rejections for "code quality" because of (and I quote) "looks like a useless AI slop comment." This is something models still do, but that is also very easily fixable. I think in that case the issue is that the level of comment wanted hasn't been properly formalized in the repo and the model hasn't been able to deduce it from the context it had.

As for the article, I think mixing all models together doesn't make sense. For example, maybe a slope describe the increasing Claude Sonnet better than a step function.

Re: Are LLM merge rates not getting better?

#68
post #62

I think what happened with static image generation is happening with LLMs. Basically the tools around are becoming better, but all the AI improvements stall, the error rate stay the same (but external tools curate the results so it won't be noticeable if you don't run your own model), the accuracy is still slightly improving, but slower and slower, and never reach the 'perfect' point. Basically stablediffusion early…

Image quality has improved a lot in recent months thanks to better models. The ability of people to notice these improvements is plateauing because they are not trained to spot artifacts, which are becoming more obscure.

Re: Are LLM merge rates not getting better?

#69

I don't find this very compelling. If you look at the actual graph they are referencing but never showing [1] there is a clear improvement from Sonnet 3.7 -> Opus 4.0 -> Sonnet 4.5. This is just hidden in their graph because they are only looking at the number of PRs that are mergable with no human feedback whatsoever (a high standard even for humans). And even if we were to agree that that's a reasonable standard, G…

Yes, I think this is basically an instance of the "emergent abilities mirage." https://arxiv.org/abs/2304.15004

If you measure completion rate on a task where a single mistake can cause a failure, you won't see noticeable improvements on that metric until all potential sources of error are close to being eliminated, and then if they do get eliminated it causes a sudden large jump in performance.

That's fine if you just want to know whether the current state is good enough on your task of choice, but if you also want to predict future performance, you need to break it down into smaller components and track each of them individually.

Re: Are LLM merge rates not getting better?

#70
post #46

Benchmaxxing aside, if you are using those tools for programming on a regular basis it should be self-evident that they are improving. I find it very hard to believe that someone using LLMs today vs what was available one year ago (Claude Code released Feb 2025) would have any difficulty answering this question.

I think it is important to try to find more rigorous things to test than the general sentiment of the people using the tools. If only because the more benchmarks we have the more we can improve models without regressions. METR is asking a really interesting question here, "are models improving at making one shot PRs?". The answer seems to be, yes, but slower than benchmarks suggest, if you look at the pass rate of different versions of Claude Sonnet. A reasonable answer is "you're not supposed to use them by making one shot PRs", but then ideally we would need to have some kind of standarized test for the ability of models to incorporate feedback and evolve PRs.
Post reply on HN