rust-best-practices

rust-best-practices is a skill for Claude Code from scott-fryxell/brayness. It costs 48 tokens per session (884 once invoked), scanned A, original, MIT.

A guide to writing Rust code in the customary style, covering ownership, borrowing, errors, performance, linting, and tests. It is based on Apollo GraphQL's Rust practices.

In plain words
What is it for?
Use it when writing, reviewing, or refactoring Rust code, including its error handling, performance, lint warnings, and tests.
Why use it?
It helps avoid unclear or error-prone Rust code, especially when deciding how values are shared and how failures are handled.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Good fit Use it when writing, reviewing, or refactoring Rust code, including its error handling, performance, lint warnings, and tests.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/scott-fryxell/brayness/rust-best-practices
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 scott-fryxell/brayness --skill rust-best-practices
Clone the repo
git clone --depth 1 https://github.com/scott-fryxell/brayness

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 rust-best-practices

README.md
[![agentmods](https://agentmods.dev/badge/skills/scott-fryxell/brayness/rust-best-practices/github.svg)](https://agentmods.dev/skills/scott-fryxell/brayness/rust-best-practices)
Your own site
<a href="https://agentmods.dev/skills/scott-fryxell/brayness/rust-best-practices"><img src="https://agentmods.dev/badge/skills/scott-fryxell/brayness/rust-best-practices/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 rust-best-practices

Your own site · 80×15
<a href="https://agentmods.dev/skills/scott-fryxell/brayness/rust-best-practices"><img src="https://agentmods.dev/badge/skills/scott-fryxell/brayness/rust-best-practices.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 48 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 884 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.
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 $0.00048 $0.00884
Opus 5 $0.00024 $0.00442
Sonnet 5 $0.00010 $0.00177
Haiku 4.5 $0.00005 $0.00088

Measured 11d ago against content hash 07579d8611fc, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

rust-best-practices 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.

skills/rust-best-practices/SKILL.md · 76 lines

How it starts

The opening of the file, as written. The whole thing — 76 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Rust Best Practices

Apply these guidelines when writing or reviewing Rust code. Based on Apollo GraphQL's Rust Best Practices Handbook.

Best Practices Reference

Before reviewing, familiarize yourself with Apollo's Rust best practices. Read ALL relevant chapters in the same turn in parallel. Reference these files when providing feedback:

Trimmed to the chapters that apply here. The only Rust in this workspace is work/realness/tracer, a ~300-line WASM cdylib with no threads, no unsafe, no trait objects, and no published rustdoc API. Apollo's chapters 6-9 (generics and dispatch, type state, comments vs documentation, pointers and Send/Sync) were dropped as inapplicable. Pull them from the upstream handbook if a future crate needs them.

Quick Reference

Borrowing & Ownership

  • Prefer &T over .clone() unless ownership transfer is required
  • Use &str over String, &[T] over Vec<T> in function parameters
  • Small Copy types (24 bytes or less) can be passed by value
  • Use Cow<'_, T> when ownership is ambiguous

Error Handling

  • Return Result<T, E> for fallible operations; avoid panic! in production
  • Never use unwrap()/expect() outside tests
  • Use thiserror for library errors, anyhow for binaries only
  • Prefer ? operator over match chains for error propagation

Read the full file on GitHub · 76 lines

Files

What ships with it

5 files 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 · 76 lines · 48 tokens per session scan A 07579d8611fc

Subscribe to this mod's changes

rust-best-practices is a skill published in the GitHub repository scott-fryxell/brayness (122 stars, last pushed 2d ago), licensed MIT. It adds 48 tokens to every session and 884 once invoked, about $0.0002 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.