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.
npx skills add fusengine/agents --skill rust-ecosystem-cratesgit clone --depth 1 https://github.com/fusengine/agentsWrote 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/fusengine/agents/rust-ecosystem-crates)<a href="https://agentmods.dev/skills/fusengine/agents/rust-ecosystem-crates"><img src="https://agentmods.dev/badge/skills/fusengine/agents/rust-ecosystem-crates/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/fusengine/agents/rust-ecosystem-crates"><img src="https://agentmods.dev/badge/skills/fusengine/agents/rust-ecosystem-crates.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Excessive Agency · line 134 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
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 | $0.00048 | $0.01366 |
| Opus 5.5 | $0.00019 | $0.00546 |
| Sonnet 5.5 | $0.00010 | $0.00273 |
| Haiku 4.5 | $0.00005 | $0.00137 |
Grade A, and why
rust-ecosystem-crates 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.
How it starts
The opening of the file, as written. The whole thing — 137 lines — stays where its author put it; the contents beside it link to each section on GitHub.
It also covers matching an existing project's Cargo.toml conventions before introducing a competing crate, and the version-verification discipline (never trust a remembered patch number; confirm current versions on crates.io/Context7/Exa).
Out of scope: once a crate is chosen, its detailed API usage belongs to the matching domain skill (rust-web-backend, rust-async-concurrency, rust-error-handling) or direct docs verification (docs.rs/crates.io → Context7 → Exa).
Rust Ecosystem & Crates
Agent Workflow (MANDATORY)
Before ANY crate selection, spawn 3 agents in parallel, one Agent call each with a name:
- fuse-ai-pilot:explore-codebase - Read existing
Cargo.tomlto match established choices - fuse-ai-pilot:research-expert - Confirm the CURRENT version + maintenance status on crates.io via Context7/Exa
- mcp__context7__query-docs - Pull the chosen crate's current API before writing code
After implementation, run fuse-ai-pilot:sniper for validation.
Overview — the decision map
| Domain | De-facto standard (2026) | Reach for it when |
|---|---|---|
| Serialization | serde (+ serde_json) |
Any (de)serialization; derive Serialize/Deserialize |
| CLI parsing | clap (derive API) |
Argument parsing, subcommands, help generation |
| Async runtime | tokio |
Almost all async I/O; the ecosystem default |
| Web framework | axum |
HTTP servers on tokio + tower middleware |
| HTTP client | reqwest |
Outbound HTTP, JSON, TLS |
| Database | sqlx / sea-orm / diesel |
See db-and-async.md for the choice |
| Error (libraries) | thiserror |
Typed error enums in a library's public API |
| Error (apps) | anyhow |
Ergonomic Result with context in binaries |
| Observability | tracing (+ tracing-subscriber) |
Structured, async-aware logs and spans |
What ships with it
4 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 Changed 8b033e5ff983
- 1mo ago First seen · 137 lines · 48 tokens per session scan A 5c041edf2861
rust-ecosystem-crates is a skill published in the GitHub repository fusengine/agents (33 stars, last pushed 7d ago), licensed MIT. It adds 48 tokens to every session and 1,366 once invoked, about $0.0002 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 2026-09-03.
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