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AGENTS.md: there to increase your costs

2026-08-31 18:14:50.517544+02 by Dan Lyke 2 comments

Evaluating AGENTS.md: Are Repository-Level Context Files Helpful for Coding Agents?

Surprisingly, we find that providing context files does not generally improve task success rates, while increasing inference cost by over 20% on average. This observation holds across different LLMs, coding agents, and for both LLM-generated and developercommitted context files. Specifically, we find that while instructions in the context files are well followed by coding agents, repository overviews, although popular and recommended by model providers, are not helpful. We conclude that while context files are useful for specifying non-standard coding practices, any attempts to improve performance should be rigorously evaluated before deployment.

[ related topics: Software Engineering Theater & Plays ]

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#Comment Re: made: 2026-08-31 19:16:36.678876+02 by: markd

> should be rigorously evaluated

Why start now?

#Comment Re: made: 2026-08-31 20:32:00.006256+02 by: Dan Lyke

Oh snap!

This is one of the things I think about a lot in software: we do a crap job of measuring productivity, and we adopt a whole lot of practices that make people (generally not the actual developers) feel good, practices that I strongly suspect are shit for productivity.

I strongly suspect that LLM and "agent" use is such a practice, but I have no data, and no way to gather data.

Only vibes.

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