Reverse Engineering Codex CLI to Get GPT-5-Codex-Mini to Draw Me a Pelican

> This is a useful starting point for a project like this—in figuring out the compile step the coding agent gets seeded with a little bit of relevant information about the project, and if it can compile that means it can later partially test the code it is writing while it works.

"Figure out how to build this" is a shortcut for getting a coding agent primed for future work. If you look at the transcript you can see what it did: https://gistpreview.github.io/?ddabbff092bdd658e06d8a2e8f142...

  • Ran ls
    └ AGENTS.md
      CHANGELOG.md
        +13 lines
      scripts
      sdk
  
  • Ran cat README.md
    └ <p align="center"><code>npm i -g @openai/codex</code><br />or <code>brew
      install --cask codex</code></p>
  
        +105 lines
  
      This repository is licensed under the [Apache-2.0 License](LICENSE).
  
  • Ran rg -n "rust" -n docs/install.md
    └ 23:curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
      25:rustup component add rustfmt
      26:rustup component add clippy
  
  • Ran sed -n '1,200p' docs/install.md
    └ ## Install & build
  
        +36 lines
      cargo test
      ```
  
  • I’m gathering the build steps for the Rust tool, focusing on running cargo
    build inside the codex-rs directory. I'll check dependencies and confirm
    the instructions before actually building, aiming to provide a clear summary
    afterward.
  
  • Ran cargo build
    └     Updating git repository `https://github.com/nornagon/crossterm`
          Updating git repository `https://github.com/nornagon/ratatui`
        +825 lines
         Compiling codex-cli v0.0.0 (/Users/simon/Dropbox/dev/codex/codex-rs/cli)
          Finished `dev` profile [unoptimized + debuginfo] target(s) in 1m 27s
  
  • Ran ls target/debug | head
    └ apply_patch
      apply_patch.d
        +6 lines
      codex-execpolicy

I might learn Rust some day. At the moment, I don't need the mental clutter.

Regarding your second point, I think people actually underutilise LLMs for simple tasks. Delegating these tasks frees up your problem-solving skills for challenges that truly need human insight. In this case, asking an LLM is arguably the smart choice: it's a common task in training data, easy to verify, and low-risk to run and not a direct learning or benefit for your initial question.

It is easy for any of us to quickly bootstrap a new project in whatever language. But this takes a cognitive toll, and adds friction to bring our visions online.

Recently, I went "blind" for a couple of days. My vision was so damaged I could only see blurs. The circumstances of this blindness are irrelevant, but it dawned on me that if I were blind, I could no longer code as I do.

This realization led me to purchase a Max subscription to Claude Code and rely more on LLMs for building, not less.

It was much more effective than I thought it would be. In my blurred blindness, I saw blobs of a beautiful user interface form, from the skeleton of my Rust backend, Vue3 frontend. It took my (complex backend in Rust) and my frontend scaffolding to another level. I could recognize it via the blur distinctly. And it did this in minutes / hours instead of days.

As my vision returned, I began analyzing what happened and conducting experiments. My attitude changed completely. Instead of doing things myself, directly, I set out to make the LLM do it, even if it took more time.

It is painful at first. It makes very stupid mistakes that make an experienced engineer snarl at it, "I can do better myself". But my blindness gave me new sight. If I were blind, I couldn't do it myself. I would need help.

Instead of letting that ego take over, I started patiently understanding how the LLM best operates. I discovered mainly it needs context and specific instructions.

I experimented with a DSL I made for defining LLM instructions that are more suited for it, and I cannot describe the magic that started unfolding.

Now, I am writing a massive library of modular instructions for LLMs, and launching them against various situations. They will run for hours uninterrupted and end up implementing full code bases, with complete test suites, domain separation, and security baked in.

Reviewing their code, it looks better than 90% of what I see people producing. Clear separation of concerns, minimal code reuse, distinct interface definitions, and so much more.

So now, I have been making it more and more autonomous. It doesn't matter if I could bootstrap a project in 30 seconds. If I spend a few hours perfecting the instructions to the LLM, I can bootstrap ANY project for ANY LANGUAGE, forever.

And the great thing? I already know the pattern works. At this point, it is foolish for me to do anything other than this.

Why would that be true? The average assistant is certainly typing more quickly than their boss, but most people would not find issue in that. It's different responsibilities. You free up time to research / problem-solve other things.

> No need to wait for 5-30 minutes until LLM figures this out.

I don't care it the LLM takes 15 additional minutes to figure it out, if it net saves me a minute (we could certainly debate the ergonomics of the multitasking involved, but that is something that every person, who delegates work, has to deal with and that's not unique to working with LLMs in any way)

That's one way to think about it, but on the other hand, where's the "skill" in knowing a particular CLI invocation for a particular tool or installation task? Next year there will be a Better Way to Do It. (Witness how many trendy package installers / venv managers the Python community has gone through.)

An LLM's job is to translate what I want to do into instructions or commands that actually do it. Real skill involves defining and directing the process; the implementation details are just temporary artifacts. Memorized command lines, mastery of specific tools, and conflation of rote procedures with "skills" are what keeps languages like C around for 50 years, long after the point where they begin to impede progress.

It's not that I don't care about learning how to build Rust or think that it's too big of a challenge. It's just not the thing I was excited about right now, and it's not obvious ahead of time how sidetracked it will get me. I find that having an LLM just figure it out helps me to not lose momentum.

It's a very bad threshold. The models write the plain SVG without looking at the final image. Humans would be awful at it and you would mistakenly conclude that they aren't general intelligences.