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Improving 15 LLMs at Coding in One Afternoon. Only the Harness Changed

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41–50 of 318 posts

Re: Improving 15 LLMs at Coding in One Afternoon. Only the Harness Changed

#41
post #20

Earlier quoted context omitted.

At this point subsidizing Chinese open-weights vendors by paying for them is just the right thing to do. Maybe they too might go closed-weights when they become SotA, but they're now pretty close and haven't done it.

I am wondering what kinds of harness are best for GLM, Deepseek, Qwen, Kimi.

OpenCode is great in general. At least one of them is specifically trained on CC - I think it was Qwen - so for those that should give best results.

Re: Improving 15 LLMs at Coding in One Afternoon. Only the Harness Changed

#43

Great work, but concurrency is lost. With search-replace you could work on separate part of a file independently with the LLM. Not to mention with each edit all lines below are shifted so you now need to provide LLM with the whole content. Have you tested followup edits on the same files?

Serializing writes is probably fine and the hashes should only change if you're updating the same line, right?

You probably don't want to use the line number though unless you need to disambiguate

But your write tool implementation can take care of that

Re: Improving 15 LLMs at Coding in One Afternoon. Only the Harness Changed

#44

Earlier quoted context omitted.

Which, IMHO, should be why we should be able to change them freely or make our own. Being locked into a specific harness because you pay 20 bucks per month vs. pay-per-use ... is kinda dumb.

Also another place where having it change out from underneath you can drastically alter the quality of your work in unexpected ways. Like most things - assume the "20/100/200" dollar deals that are great now are going to go down the enshitification route very rapidly. Even if the "limits" on them stay generous, the product will start shifting to prioritize things the user doesn't want. Tool recommendations are my imm…

> Like most things - assume the "20/100/200" dollar deals that are great now are going to go down the enshitification route very rapidly.

I don’t assume this at all. In fact, the opposite has been happening in my experience: I try multiple providers at the same time and the $20/month plans have only been getting better with the model improvements and changes. The current ChatGPT $20/month plan goes a very long way even when I set it to “Extra High” whereas just 6 months ago I felt like the $20/month plans from major providers were an exercise in bouncing off rate limits for anything non-trivial.

Inference costs are only going to go down from here and models will only improve. I’ve been reading these warnings about the coming demise of AI plans for 1-2 years now, but the opposite keeps happening.

Re: Improving 15 LLMs at Coding in One Afternoon. Only the Harness Changed

#45
post #6

The harness matters far more than most people think. This post about the CORE benchmark where Opus’ score almost doubled when they switched to Claude Code from their own harness. https://x.com/sayashk/status/1996334941832089732

Which, IMHO, should be why we should be able to change them freely or make our own. Being locked into a specific harness because you pay 20 bucks per month vs. pay-per-use ... is kinda dumb.

> Being locked into a specific harness because you pay 20 bucks per month vs. pay-per-use ... is kinda dumb.

I’ll probably get downvoted for this, but am I the only one who thinks it’s kind of wild how much anger is generated by these companies offering discounted plans for use with their tools?

At this point, there would be less anger and outrage on HN if they all just charged us the same high per-token rate and offered no discounts or flat rate plans.

Re: Improving 15 LLMs at Coding in One Afternoon. Only the Harness Changed

#46
post #37

Earlier quoted context omitted.

I was under the impression that they do obey robots.txt now? There are clearly a lot of dumb agents that don’t, but didn’t think it was the major AI labs.

After 3 years of pirating and scraping the entire world by doing the above, I guess they have everything that they now need or want. So then it's better to start obeying ROBOTS.txt as a ladder pull through a "nicely behaved" image advantage.

Obeying robots.txt (now) is still better than not obeying it, regardless of what they did before.

The alternative is to say that bugs shouldn’t be fixed because it’s a ladder pull or something. But that’s crazy. What’s the point of complaining if not to get people to fix things?

Re: Improving 15 LLMs at Coding in One Afternoon. Only the Harness Changed

#48
I ran into this from the other direction. I built a small SRE agent for my cloud infra and just kind of walked into hand-rolling some of the tools rather than using what exists today. I provided an edit_file tool that felt like it was of reasonable capability, but in practice the agent was regularly 'trying' to do a one line change and submitting PRs that hallucinated 3/4s of the file.

Seeing how bad the results are when you're casually approaching something makes it very evident that it's a topic that can be optimized.

Re: Improving 15 LLMs at Coding in One Afternoon. Only the Harness Changed

#49
post #30

Shows how much room for improvement there is on the harness level. Agents waste a lot of tokens on editing, sandboxes, passing info back and forth from tool calls and subagents. Love the pragmatic mix of content based addressing + line numbers. Beautiful.

i haven't dug into the article but your comment reminded me about the ClaudeCode Superpowers plugin. I find the plugin great but it's quite "expensive", I use the pay-as-you-go account with CC because i've just been trying it out personally and the superpowers plugin spends a lot of money, relative to regular CC, with all the back and forth.

With CC you can do a /cost to see how much your session cost in dollar terms, that's a good benchmark IMO for plugins, .md files for agents, and so on. Minimize the LLM cost in the way you'd minimize typical resource usage on a computer like cpu, ram, storage etc.

Re: Improving 15 LLMs at Coding in One Afternoon. Only the Harness Changed

#50

My experience as well. People worry our profession is being reduced to "prompt engineer", but actually I get the feeling that programming will soon be mainly about designing and building harnesses for specific tasks.

Personal opinion is that LLMs are definitely not as magical as people think they are, they fill a specific niche of problem-solving, and harnesses are necessary to corral your problem into the niche that they are extremely good at solving.
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