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Re:Show HN: How to Build a Coding Agent (free workshop) by ofirpress on Saturday August 23, 2025 @11:55PM (#45001234)
We (the Princeton SWE-bench team) built an agent in ~100 lines of code that does pretty well on SWE-bench, you might enjoy it too: https://github.com/SWE-agent/mini-swe-agent
Re:Show HN: How to Build a Coding Agent (free workshop) by ghuntley on Sunday August 24, 2025 @12:05AM (#45001287)
cheers i'll add it in.
Re:Show HN: How to Build a Coding Agent (free workshop) by simonw on Sunday August 24, 2025 @01:06AM (#45001548)
OK that really is pretty simple, thanks for sharing.

The whole thing runs on these prompts: https://github.com/SWE-agent/mini-swe-agent/blob/7e125e5dd49...

  Your task: {{task}}. Please reply
  with a single shell command in
  triple backticks.
  
  To finish, the first line of the
  output of the shell command must be
  'COMPLETE_TASK_AND_SUBMIT_FINAL_OUTPUT'.
Re:Show HN: How to Build a Coding Agent (free workshop) by nivertech on Sunday August 24, 2025 @03:58AM (#45002285)

  system_template: str = "You are a helpful assistant that can do anything."
anything? Sounds like an AI Safety issue ;)
Re:Show HN: How to Build a Coding Agent (free workshop) by greleic on Sunday August 24, 2025 @09:52AM (#45004257)
You’d be surprised at the amount of time wasted because LLMs “think” they can’t do something. You’d be less surprised that they often “think” they can’t do something, but choose some straight ignorant path that cannot work.

There are theoretically impossible things to do, if you buy into only the basics. If you open your mind, anything is achievable; you just need to break out of the box you’re in.

If enough people keep feeding in that we need a time machine, the revolution will play out in all the timelines. Without it, Sarah Connor is lost.

Re:Show HN: How to Build a Coding Agent (free workshop) by curvaturearth on Sunday August 24, 2025 @07:59PM (#45008927)
I'm already surprised by the amount of things they think they can do but can't
Re:Show HN: How to Build a Coding Agent (free workshop) by sireat on Sunday August 24, 2025 @05:20AM (#45002729)
Pretty sure you also need about 120 lines of prompting from default.yaml

https://github.com/SWE-agent/mini-swe-agent/blob/7e125e5dd49...

Re:Show HN: How to Build a Coding Agent (free workshop) by faangguyindia on Sunday August 24, 2025 @01:46AM (#45001716)
when a problem is entirely self contained in a file, it's very easy to edit it with LLM.

that's not the case with a codebase, where things are littered around in tune with specific model of organisation the developer had in mind.

Re:Show HN: How to Build a Coding Agent (free workshop) by fmbb on Sunday August 24, 2025 @03:16AM (#45002076)
Re:Show HN: How to Build a Coding Agent (free workshop) by koakuma-chan on Sunday August 24, 2025 @01:48AM (#45001723)
> in tune with specific model of organisation

You wish

Re:Show HN: How to Build a Coding Agent (free workshop) by meander_water on Sunday August 24, 2025 @01:51AM (#45001737)
> 1. Analyze the codebase by finding and reading relevant files 2. Create a script to reproduce the issue 3. Edit the source code to resolve the issue 4. Verify your fix works by running your script again 5. Test edge cases to ensure your fix is robust

This prompt snippet from your instance template is quite useful. I use something like this for getting out of debug loops:

> Analyse the codebase and brainstorm a list of potential root causes for the issue, and rank them from most likely to least likely.

Then create scripts or add debug logging to confirm whether your hypothesis is correct. Rule out root causes from most likely to least by executing your scripts and observing the output in order of likelihood.

Re:Show HN: How to Build a Coding Agent (free workshop) by afro88 on Sunday August 24, 2025 @03:30PM (#45006960)
Does this mean it's only useful for issue fixes?
Re:Show HN: How to Build a Coding Agent (free workshop) by regularfry on Sunday August 24, 2025 @05:43PM (#45008077)
A feature is just an issue. The issue is that the feature isn't complete yet.
Re:Show HN: How to Build a Coding Agent (free workshop) by afro88 on Monday August 25, 2025 @07:04AM (#45012539)
> 2. Create a script to reproduce the issue

Surely that would send it a bit off the rails to implement a feature?

Re:Show HN: How to Build a Coding Agent (free workshop) by regularfry on Monday August 25, 2025 @10:47AM (#45014461)
Sounds like an acceptance test to me!
Re:Show HN: How to Build a Coding Agent (free workshop) by afro88 on Monday August 25, 2025 @04:00PM (#45018294)
True. I guess I should actually try it out :)
Re:Show HN: How to Build a Coding Agent (free workshop) by Teever on Sunday August 24, 2025 @03:13AM (#45002061)
What sort of results have you had from running it on its own codebase?
Re:Show HN: How to Build a Coding Agent (free workshop) by BenderV on Sunday August 24, 2025 @03:27AM (#45002110)
Nice but sad to see lack of tools. Most your code is about the agent framework instead of specific to SWE.

I've built a SWE agent too (for fun), check it out => https://github.com/myriade-ai/autocode

Re:Show HN: How to Build a Coding Agent (free workshop) by diminish on Sunday August 24, 2025 @03:32AM (#45002134)
> sad to see lack of tools.

Lack of tools in mini-swe-agent is a feature. You can run it with any LLM no matter how big or small.

Re:Show HN: How to Build a Coding Agent (free workshop) by BenderV on Sunday August 24, 2025 @05:38AM (#45002821)
I'm trying to understand what does it got to do with LLM size? Imho, right tools allow small models to perform better than undirected tool like bash to do everything. But I understand that this code is to show people how function calling is just a template for LLM.
Re:Show HN: How to Build a Coding Agent (free workshop) by diminish on Sunday August 24, 2025 @06:52AM (#45003155)
Mini swe agent, as an academic tool, can be easily tested aimed to show the power of a simple idea against any LLM. You can go and test it with different LLMs. Tool calls didn't work fine with smaller LLM sizes usually. I don't see many viable alternatives less than 7GB, beyond Qwen3 4B for tool calling.

> right tools allow small models to perform better than undirected tool like bash to do everything.

Interesting enough the newer mini swe agent was refutation of this hypothesis for very large LLMs from the original swe agent paper (https://arxiv.org/pdf/2405.15793) assuming that specialized tools work better.

Re:Show HN: How to Build a Coding Agent (free workshop) by BenderV on Monday August 25, 2025 @05:29AM (#45011950)
Thanks for your answer.

I guess that it's only a matter of finetuning.

LLM have lots of experience with bash so I get they figure out how to work with it. They don't have experience with custom tools you provide it.

And also, LLM "tools" as we know it need better design (to show states, dynamic actions).

Given both, AI with the right tools will outperform AI with generic and uncontrolled tool.

Re:Show HN: How to Build a Coding Agent (free workshop) by zhlmmc on Sunday August 24, 2025 @11:02PM (#45009789)
Totally understandable. General coding agent is 95% from the model.