My agent.md to improve LLM-assisted code quality

(fabiensanglard.net)

63 points | by ibobev 3 hours ago

13 comments

  • eschaton 1 minute ago
    I didn’t see anything in there instructing the LLM not to generate text about goblins.
  • tomr75 3 minutes ago
    I think this is dated. I wonder if the author has tried codex/other harnesses
  • OptionOfT 1 hour ago
    A bunch of these should be enforce with linting, that way people who still hand-craft code get the same kind of feedback, e.g. Always use {}, even on a one-line "if" statement. & Keep function names short. Less than 30 characters.

    Then this one really is a pattern that creates a lot of churn:

    - Add a small, to the point, comment to explain what the block does and why. Use examples when possible. Propose ASCII drawings to explain complete systems.

    The what _is_ the code.

    • getnormality 1 hour ago
      I would never tell an agent to write "what does the code do" comments. Their default comments are already way too fluffy.
      • rustystump 27 minutes ago
        I added to the memory, system prompts, and the prompt itself and every soa model still litters code with the most inane useless crap. I will then get code to review from a coworker using fable/opus. It has more lines of comments then code.

        Maybe I am some god tier code reader (i am not) but i dont think i have ever found a comment in code to be useful in my day job. That isnt true, i once came across

        // submit to the dark lord

        Above the function that sent a payment to PayPal for processing. It made me laugh so I let it be.

  • newsomix9xl 35 minutes ago
    A great piece.

    I esp liked:

    "- Don't touch blocks of code unrelated to the feature you implement. e.g. Don't add comments to a block of code if you did not create it or modify it. As much as possible try to minimize the number of changed lines when implementing a feature."

    The feature where you ask the LLM to fix one thing and it fixes three things.

    I kept noticing this in diffs.

  • oumua_don17 1 hour ago
    Just this one line in AGENTS.md has given better results to reduce if not eliminate verbosity and grandeur.

    **Always use ASD-STE100 Simplified Technical English

    Disclaimer: I saw this listed in some other HN post that I can' locate right away.

    • mattjoyce 20 minutes ago
      This will produce quite verbose prose. STE100 is good for specs and explanations but it works best with a glossary or terms. will burn tokens.
    • wpasc 1 hour ago
      idk who came up with it first, but ASD-STE100 has been floating around more since matt pocock put it in one of his skills
  • YuechenLi 1 hour ago
    Since we are sharing our AGENTS.md, I thought I'd share my own, because most of the time, this is pretty much all you need for LLMs to write good code, everything else can be added per project: ---- *Convergence rule* Every substantial task must end in exactly one of three states:

    A. Success The intended capability works in the real path and the real motivating case materially improves.

    B. Meaningful progression The capability is not complete, but one genuine blocker is removed and the next blocker is isolated with evidence.

    C. Honest stop Further work would require overbroad scope expansion, excessive debt, brittle patching, or tangled logic. Stop and report the reason with concrete evidence.

    Do not continue producing patches once the work stops converging.

    Do not confuse activity with progress. A failed attempt is only acceptable if it leaves behind a narrower problem, stronger evidence, or a justified stop.

    Any partial work must leave the codebase in a cleaner, more legible, and more diagnosable state than before. ----

    A lot of the article's AGENTS.md just feel like telling the LLM agents either something they already know (for example, most of the time they know to use exhaustive switch/match statements instead of "arrow anti-pattern") or seems actively harmful ("keep function names short" seems arbitrary and may cause the LLMs to write weird abbreviations for functions that are harder to read and review.

    • lelanthran 46 minutes ago
      > but one genuine blocker is removed and the next blocker is isolated with evidence.

      What's the difference between a "genuine blocker" and a "blocker"? Why is the next blocker not genuine? Does it become genuine only after isolation?

      • YuechenLi 40 minutes ago
        "Genuine blocker" is mostly there because otherwise LLMs may consider the smallest thing that they couldn't immediately figure out to be blockers and stop without implementing anything. The rule is there to tell the LLM if they can figure out how to resolve the blocker by themselves, they don't have to ask me to help resolve the blocker.
  • getnormality 1 hour ago
    This is a problem that people mostly have to solve themselves. Like, I've been working with Claude for almost a year now and I have never once seen it write "Arrow Anti-Pattern" code. That, and much of the rest, would be fluff in my projects. Agent instructions are best learned from experience project-by-project.
  • Geee 1 hour ago
    I feel like claude.md is like Asimov's laws of robotics. Whatever you write there ends up eventually messing up everything.
  • Luker88 1 hour ago
    I had good results with making it add a few lines with a summary of RFC 2119/8147 keywords (SHALL/MUST...), and then using those, uppercase.

    local llm remain more in line like that.

  • FooBarWidget 1 hour ago
    One tactic I’ve found helpful is multi pass quality improvement. First make it work. Then review for guidelines adherence. Loop until satisfied.
  • bellowsgulch 1 hour ago
    I've read a few of these over the years, and none of them seem to be useful. I have three sentences in my custom instructions, and those are basically all useless, too.

    Even my second one, "Avoid decorative or section-header comments. Never use `----` or `====` as comment separators. Comments should explain only non-obvious behavior, rationale, constraints, or implementation details." seems to be ignored by models regularly, so I don't see the point.

    But this is in my private harness. Perhaps other harnesses have better instruction following. My custom instructions are prepended to my first user message, not set as a system message.

    • dan_ggggg 30 minutes ago
      > I've read a few of these over the years, and none of them seem to be useful.

      AI users are overwhelmingly addicts who are lying to themselves and the people around them. I've lost patience for their kind.

  • dude250711 59 minutes ago
    It seems like everyone goes through a detailed AGENTS.md phase.
  • acedTrex 1 hour ago
    Agents.md is such a ridiculous concept, just write good contributing docs and then optionally @ the file in whatever agetn file you use.

    That way everyone benefits.

    • FooBarWidget 1 hour ago
      No, why should I have to remember to @ in every prompt? Or ask contributors to remember. It just makes it easier to make human mistakes. I have better things to do than micromanagement. There is huge value in auto-included context.
      • anygivnthursday 1 hour ago
        The GP wrote @ it from the agents.md file, not from the prompt. Their point was that instead of writing "how to contribute" instructions for agents, you could explain that in the CONTRIBUTING.md and link it from your agents file, so both humans and agents read it from one place.
        • formerly_proven 35 minutes ago
          Symlinks exist, but it's kind of ridiculous all harnesses just ignore CONTRIBUTING, HACKING and friends.
      • acedTrex 1 hour ago
        You put the @ in the context file the LLMs all use, claudemd agentsmd whatever the thing that most harnesses force load.

        Then the model will go discover what it needs to.