category-master SKILL.md skillA
category-master from hermeticormus/claude-code-game-development is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add hermeticormus/claude-code-game-development/category-master@git:20251123.bdf515dPins git:20251123.bdf515d in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- hermeticormus/claude-code-game-development
- Path
tools/meta-prompting-framework/skills/category-master/SKILL.md- Versions recorded
- 1
- Latest version
- git:20251123.bdf515d, committed Nov 23, 2025
- Size
- 33,277 bytes
- Repository stars
- 72
- License
- MIT
Expert-level category theory knowledge for rigorous mathematical reasoning. Use when working with categorical structures, functors, natural transformations, adjunctions, limits, toposes, monoidal categories, enriched categories, higher categories, operads, or any formal categorical construction. Ideal for proofs, diagram chases, universal properties, coherence conditions, and foundational mathematical abstractions.
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
# Category Master Expert guidance for rigorous categorical reasoning, proofs, and constructions in pure mathematics. ## Core Principles ### Set-Theoretic Foundations **Size distinctions** (essential for avoiding paradoxes): - **Small set**: Element of a fixed Grothendieck universe 𝒰 - **Small category**: Ob(𝒞) and all Hom-sets are small (elements of 𝒰) - **Locally small category**: Each Hom(A,B) is small, but Ob(𝒞) may be a proper class - **Large category**: Even some Hom-sets may be proper classes **Grothendieck universes**: Sets closed under standard operations (pairing, power set, unions), satisfying axioms that enable treating "all small sets" as a category without Russell-type paradoxes. **Practical implications**: - The category **Set** of all sets is not small; working in **Set** requires 𝒰 - Yoneda embedding 𝒞 → [𝒞^op, Set] requires 𝒞 locally small - Functor categories [𝒞, 𝒟]: if 𝒞 small and 𝒟 locally small, then [𝒞, 𝒟] is locally small - Adjunctions F ⊣ G: natural bijection Hom(F(A), B) ≅ Hom(A, G(B)) requires local smallness **Universe hierarchy** (for categories of categories): - When working with Cat, need 𝒰 ∈ 𝒰' ∈ 𝒰'' ... …
Read the whole file at its exact version.
How to install
mdr add hermeticormus/claude-code-game-development/category-master@sha256:082f7774c91c687aThe line at the top of this page pins the label git:20251123.bdf515d, 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_5rh7csepniawc4mg)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Nov 23, 2025.
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 (33277 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
hermeticormus/claude-code-game-development · 72 stars · license MIT · pushed 2026-10-04 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_5rh7csepniawc4mg GET https://markdownregistry.com/api/v1/resolve?ref=hermeticormus/claude-code-game-development/category-master GET https://markdownregistry.com/api/v1/blob/082f7774c91c687a466ed0ebf3a8fe73a6b42522a36a9286895fc4f2b5db45d5
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.