Borrowing it
Nothing to install: this file belongs to apollographql/apollo-mcp-server. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/apollographql/apollo-mcp-server/main/.agents/skills/rust-best-practices/SKILL.mdgit clone --depth 1 https://github.com/apollographql/apollo-mcp-serverWrote 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.
[](https://agentmods.dev/skills/apollographql/apollo-mcp-server/rust-best-practices)<a href="https://agentmods.dev/skills/apollographql/apollo-mcp-server/rust-best-practices"><img src="https://agentmods.dev/badge/skills/apollographql/apollo-mcp-server/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.
<a href="https://agentmods.dev/skills/apollographql/apollo-mcp-server/rust-best-practices"><img src="https://agentmods.dev/badge/skills/apollographql/apollo-mcp-server/rust-best-practices.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00091 | $0.01059 |
| Opus 5.5 | $0.00036 | $0.00424 |
| Sonnet 5.5 | $0.00018 | $0.00212 |
| Haiku 4.5 | $0.00009 | $0.00106 |
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 1mo 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.
Copies of this mod
8 near-identical copies found in the catalogue:
- rust-best-practices — 100% identical, 10 lines differ
- rust-best-practices — 100% identical, 0 lines differ
- rust-best-practices — 100% identical, 0 lines differ
- rust-best-practices — 100% identical, 0 lines differ
- rust-best-practices — 100% identical, 0 lines differ
- rust-best-practices — 100% identical, 0 lines differ
- rust-best-practices — 100% identical, 0 lines differ
- rust-best-practices — 100% identical, 0 lines differ
How it starts
The opening of the file, as written. The whole thing — 95 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:
- Chapter 1 - Coding Styles and Idioms: Borrowing vs cloning, Copy trait, Option/Result handling, iterators, comments
- Chapter 2 - Clippy and Linting: Clippy configuration, important lints, workspace lint setup
- Chapter 3 - Performance Mindset: Profiling, avoiding redundant clones, stack vs heap, zero-cost abstractions
- Chapter 4 - Error Handling: Result vs panic, thiserror vs anyhow, error hierarchies
- Chapter 5 - Automated Testing: Test naming, one assertion per test, snapshot testing
- Chapter 6 - Generics and Dispatch: Static vs dynamic dispatch, trait objects
- Chapter 7 - Type State Pattern: Compile-time state safety, when to use it
- Chapter 8 - Comments vs Documentation: When to comment, doc comments, rustdoc
- Chapter 9 - Understanding Pointers: Thread safety, Send/Sync, pointer types
Quick Reference
Borrowing & Ownership
- Prefer
&Tover.clone()unless ownership transfer is required - Use
&stroverString,&[T]overVec<T>in function parameters - Small
Copytypes (≤24 bytes) can be passed by value - Use
Cow<'_, T>when ownership is ambiguous
Error Handling
- Return
Result<T, E>for fallible operations; avoidpanic!in production - Never use
unwrap()/expect()outside tests - Use
thiserrorfor library errors,anyhowfor binaries only - Prefer
?operator over match chains for error propagation
What ships with it
9 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.
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.
- 1mo ago First seen · 95 lines · 91 tokens per session scan A 80eeb8ab3da0
rust-best-practices is a skill published in the GitHub repository apollographql/apollo-mcp-server (317 stars, last pushed 2d ago), licensed MIT. It adds 91 tokens to every session and 1,059 once invoked, about $0.0004 per session on Opus 5.5. 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.
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