greenspuns-tenth-rule SKILL.md skillA
greenspuns-tenth-rule from the-artificer-of-ciphers-llc/skills-from-the-artificer is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add the-artificer-of-ciphers-llc/skills-from-the-artificer/greenspuns-tenth-rule@git:20260530.3e17152Pins git:20260530.3e17152 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- the-artificer-of-ciphers-llc/skills-from-the-artificer
- Path
greenspuns-tenth-rule/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260530.3e17152, committed May 30, 2026
- Size
- 3,921 bytes
- Repository stars
- 6
- License
- MIT
Apply Greenspun's Tenth Rule when reviewing complex codebases that have grown their own configuration systems, rule engines, templating languages, scripting layers, or workflow DSLs. Trigger on phrases like "we built our own config language", "we have a custom rules engine", "this template system has gotten really complex", "we're basically reimplementing X ourselves", or any time a team has reinvented a programming language feature or general-purpose tool inside their application. This rule…
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Greenspun's Tenth Rule > "Any sufficiently complicated C or Fortran program contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Common Lisp." > — Philip Greenspun ## The core idea When a program grows complex enough, developers eventually need features that their current language or framework doesn't easily provide: dynamic dispatch, higher-order functions, user-configurable behavior, extensibility hooks. Rather than adopting a language or tool that has these features natively, they build them from scratch — usually badly, incompletely, and without realizing that's what they're doing. The result is a half-implemented, poorly-documented programming language or runtime lurking inside a codebase that was never meant to host one. ## What this looks like in practice - A configuration file format that has grown conditionals, loops, and variables → you've built a scripting language - A "template engine" with logic, iteration, and state → you've built a programming language - A rules engine with complex precedence and side effects → you've built an interpreter - A workflow system with retries, timeouts, and branching → you've built a runtime …
Read the whole file at its exact version.
How to install
mdr add the-artificer-of-ciphers-llc/skills-from-the-artificer/greenspuns-tenth-rule@sha256:3d32e54b0b559d8fThe line at the top of this page pins the label git:20260530.3e17152, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_2djob32tm2kiq6vu)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on May 30, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (3921 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
the-artificer-of-ciphers-llc/skills-from-the-artificer · 6 stars · license MIT · pushed 2026-11-08 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_2djob32tm2kiq6vu GET https://markdownregistry.com/api/v1/resolve?ref=the-artificer-of-ciphers-llc/skills-from-the-artificer/greenspuns-tenth-rule GET https://markdownregistry.com/api/v1/blob/3d32e54b0b559d8f643e816019723ae9837800c27a7cabed6941b183f6a3b11e
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
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