Rust Crate Discovery and Evaluation

Authority: crates.io API, docs.rs, GitHub REST API, RustSec Advisory Database.

This skill owns the discovery + evaluation phase before a crate enters your Cargo.toml. It uses a bundled Python tool (scripts/crate_eval.py) to fetch signals from 4 sources and produce a weighted 0-100 score with a letter grade (A/B/C/D/F), red-flag list, and a recommendation. It does not own post-adoption governance (rust-dependencies), manifest mechanics (rust-cargo-build), or semver (rust-semver).

Capability Boundaries

✅ Strengths

1. Search crates.io by keyword, category, or name — returns ranked candidates
2. Evaluate a single crate in depth: fetch metadata from crates.io + docs.rs + GitHub + RustSec
3. Compare 2+ crates side-by-side with subscore breakdown
4. Score each crate 0-100 across 6 dimensions: adoption (30), maintenance (25), documentation (15), maturity (15), community (10), license (5)
5. Flag red concerns: stale, advisories, no docs, low adoption with churn, single-maintainer bus factor, no source repo, license missing
6. Recommend the best fit, surfacing blocking concerns before the user adopts
7. Output as human-readable report or machine-readable JSON (for agent consumption)