65 lines of Markdown – a Claude Code sensation

65 lines of Markdown – a Claude Code sensation

Yesterday my employer organized an AI workshop. My company works a lot with AI
supported code editing; using Cursor and VS Code, GitHub Copilot. Plus we do
custom stuff using AWS Bedrock, agents using Strands and so on, all the stuff
everyone is working with nowadays.

Our facilitator explained how custom rules files can be so very helpful for AI
tooling. He linked to this extension with
Karpathy-Inspired Claude Code Guidelines
as an example. Apparently this plugin is very popular! Yesterday morning the
project had 3.5K stars and at the end of the day this already increased to
3.9K. That’s a lot of stars.

I went on to investigate what this extension actually does and found that it’s
just
one Markdown file of 65 lines long
that lays out four principles; the first one is “Think Before Coding”, added
with some packaging to make it install in Claude Code.

Publishing it as a Cursor extension

But I don’t use Claude Code, so I fired up Codex CLI and turned it into an
extension for VS Code
and for
Cursor,
which is a fork of VS Code but uses a plugin registry from the Eclipse
Foundation.

Getting the plugins published was the most work. On the ‘VS Code Marketplace’ I
am not a Verified Publisher meaning I do not get a green check mark next to
my name, and you will get a warning if you want to install my extension. And
apparently the only way to get rid of that is to wait for six months with at
least one extension published and then apply for verification. So starting
August I can apply for that and any new extensions get automatically trusted.

For Cursor the process felt very cumbersome: I had to create an account on
open-vsx.org, create an Eclipse Foundation account,
link those accounts, link to my GitHub account, sign an Eclipse agreement, and
finally create a GitHub Issue to ‘claim’ my VS Code Marketplace namespace.

Using the extension

So, what does using the extension actually feel like? Because of the
non-deterministic nature of these models, I found it hard to tell. I tried a
simple refactoring, and I had the idea that it was very reluctant in making
changes. Was the result better? I’m not really sure.

Typically, your Cursor rules would list the constraints for your environment,
explaining what coding standards to adhere to, architectural constraints and so
on. I get that, it makes sense.

I find it wild to think that a company spends millions and millions of dollars
on training a model, with tons of engineers meticulously improving output, and
then some guy comes along and writes 60 lines of text including Think before
coding in the rules and that would make all the difference.

But the original repository has almost 4,000 stars, and surely, 4,000
developers can’t be wrong?

Please try for yourself! Install the extension, don’t forget to
star my repository
and see the results.

As Paul Simon wrote: These are the days of miracle and wonder!

Discussion on Hacker News