HarnessTax: How Much Does the Harness Matter for Coding Agents?
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HarnessTax: How Much Does the Harness Matter for Coding Agents?
Unofficial Hacker News client; not affiliated with Y Combinator.
lukax · · focus · HN ↗
E.g. for editing files with Claude models you should use Edit(file_path, old_string, new_string, replace_all) but with GPT models you should use apply_patch_call(patch) (where patch is a custom patch string with custom grammar).
It appears newer models are better at narive harness tool calls and worse at custom tools that look similar to default tools.
<a href="https://lucumr.pocoo.org/2026/7/4/better-models-worse-tools/" rel="nofollow">https://lucumr.pocoo.org/2026/7/4/better-models-worse-tools/
imtringued · · focus · HN ↗
We are still witnessing the same underlying problems of transformers.
[0] Think back to all the publicity stunts like the Hugging Face. They are meant to convince you that the agents have somehow progressed past the transformer limitations when those publicity stunts are actually expressions of transformer limitations.
wollowollo · · focus · HN ↗