The detailed compiler errors and strong type system makes the change -> compile -> change loop simple for agents to handle. Rust provides very strong rails it forces users on to. Codex always manages to get something to compile.

The downside is that maybe it should fail sometimes when an idiomatic approach isn’t viable… instead it will implement something stupid that compiles and meets the request.

The weakness of Rust WRT LLMs is compilation times. LLMs code faster and hence spend relatively more time waiting for compilation than humans do, so on reasonably sized projects (e.g. 100k+ lines) Rust's ~10x slower compilation starts showing up as a bottleneck. If you're writing some critical infrastructure it makes sense to pay that cost, but if you're writing some internal service that's not publicly exposed to the internet then development velocity may be a bigger concern. (I'd argue that slow compilation also influences human development velocity, but for some reason developers very rarely try to quantify this.)