Yes, I want that. I also want to be able to (1) statically apply a badge on every crate that makes and meets these guarantees (including transitively with that crate's own dependencies) so I can search crates.io for stronger guarantees and (2) annotate my Cargo.toml to not import crates that violate this, so time isn't wasted compiling - we know it'll fail in advance.

On the subject of this, I want more ability to filter out crates in our Cargo.toml. Such as a max dependency depth. Or a frozen set of dependencies that is guaranteed not to change so audits are easier. (Obviously we could vendor the code in and be in charge of our own destiny, but this feels like something we can let crate authors police.)