m14-mental-model

m14-mental-model is a skill for Claude Code from moeru-ai/auv. It costs 91 tokens per session (1,138 once invoked), scanned A, original, Apache-2.0.

A guide to thinking about Rust concepts such as ownership, borrowing, moves, lifetimes, and smart pointers. It uses simple mental models and comparisons with languages such as Java, C++, Python, Go, and JavaScript.

In plain words
What is it for?
Use it when learning Rust, understanding the borrow checker, reasoning about memory and cleanup, or translating concepts from another programming language.
Why use it?
It helps explain why Rust's compiler rejects certain code and replaces vague rules with an intuitive picture of who owns and lends data.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter. Also seen: installed under .agents/ (shared by several agents).

Good fit Use it when learning Rust, understanding the borrow checker, reasoning about memory and cleanup, or translating concepts from another programming language.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/moeru-ai/auv/m14-mental-model
View source ↗ moeru-ai/auv
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add moeru-ai/auv --skill m14-mental-model
Clone the repo
git clone --depth 1 https://github.com/moeru-ai/auv

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for m14-mental-model

README.md
[![agentmods](https://agentmods.dev/badge/skills/moeru-ai/auv/m14-mental-model/github.svg)](https://agentmods.dev/skills/moeru-ai/auv/m14-mental-model)
Your own site
<a href="https://agentmods.dev/skills/moeru-ai/auv/m14-mental-model"><img src="https://agentmods.dev/badge/skills/moeru-ai/auv/m14-mental-model/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for m14-mental-model

Your own site · 80×15
<a href="https://agentmods.dev/skills/moeru-ai/auv/m14-mental-model"><img src="https://agentmods.dev/badge/skills/moeru-ai/auv/m14-mental-model.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 91 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,138 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00091 $0.01138
Opus 5 $0.00046 $0.00569
Sonnet 5 $0.00018 $0.00228
Haiku 4.5 $0.00009 $0.00114

Measured 11d ago against content hash a2f9a54dc770, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

m14-mental-model scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 11d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.agents/skills/m14-mental-model/SKILL.md · 178 lines

How it starts

The opening of the file, as written. The whole thing — 178 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Mental Models

Layer 2: Design Choices

Core Question

What's the right way to think about this Rust concept?

When learning or explaining Rust:

  • What's the correct mental model?
  • What misconceptions should be avoided?
  • What analogies help understanding?

Key Mental Models

Concept Mental Model Analogy
Ownership Unique key Only one person has the house key
Move Key handover Giving away your key
&T Lending for reading Lending a book
&mut T Exclusive editing Only you can edit the doc
Lifetime 'a Valid scope "Ticket valid until..."
Box<T> Heap pointer Remote control to TV
Rc<T> Shared ownership Multiple remotes, last turns off
Arc<T> Thread-safe Rc Remotes from any room

Coming From Other Languages

From Key Shift
Java/C# Values are owned, not references by default
C/C++ Compiler enforces safety rules
Python/Go No GC, deterministic destruction
Functional Mutability is safe via ownership
JavaScript No null, use Option instead

Thinking Prompt

When confused about Rust:

  1. What's the ownership model?

    • Who owns this data?
    • How long does it live?
    • Who can access it?
  2. What guarantee is Rust providing?

    • No data races
    • No dangling pointers
    • No use-after-free
  3. What's the compiler telling me?

    • Error = violation of safety rule
    • Solution = work with the rules

Trace Up ↑

To design understanding (Layer 2):

"Why can't I do X in Rust?"
    ↑ Ask: What safety guarantee would be violated?
    ↑ Check: m01-m07 for the rule being enforced
    ↑ Ask: What's the intended design pattern?

Trace Down ↓

To implementation (Layer 1):

"I understand the concept, now how do I implement?"
    ↓ m01-ownership: Ownership patterns
    ↓ m02-resource: Smart pointer choice
    ↓ m07-concurrency: Thread safety

Read the full file on GitHub · 178 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 11d ago First seen · 178 lines · 91 tokens per session scan A a2f9a54dc770

Subscribe to this mod's changes

m14-mental-model is a skill published in the GitHub repository moeru-ai/auv (27 stars, last pushed 2d ago), licensed Apache-2.0. It adds 91 tokens to every session and 1,138 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories

rust-learner

Learn Rust language features and crate updates. Use when user asks about Rust version changelog, what's new in Rust, crate updates, Cargo.toml dependencies, tokio/serde/axum features, or any Rust ecosystem questions.

actionbook/actionbook · 51 tokens

rust-learner

Use when asking about Rust versions or crate info. Keywords: latest version, what's new, changelog, Rust 1.x, Rust release, stable, nightly, crate info, crates.io, lib.rs, docs.rs, API documentation, crate features, dependencies, which crate, what version, Rust edition, edition 2021, edition 2024, cargo add, cargo…

actionbook/rust-skills · 123 tokens

m14-mental-model

Use when learning Rust concepts. Keywords: mental model, how to think about ownership, understanding borrow checker, visualizing memory layout, analogy, misconception, explaining ownership, why does Rust, help me understand, confused about, learning Rust, explain like I'm, ELI5, intuition for, coming from Java, coming…

actionbook/rust-skills · 91 tokens

rust-daily

A reporting tool for Rust news and recurring updates, including daily, weekly, or monthly reports.

actionbook/rust-skills · 53 tokens

rust-learn

A stateful Rust learning coach that takes a learner from beginner level to independently building a tested command-line program. It teaches topics such as ownership, borrowing, traits, and concurrency through lessons, exercises, feedback, and scheduled review.

swaylq/sijiao-skill · 87 tokens

learn-rust

Use when the user wants to learn Rust interactively by exploring the sessions-chronicle codebase, guided by questions, micro-exercises, and Rust Book references.

supermaciz/sessions-chronicle · 36 tokens