An agent sends a payment request. The provider accepts it, the connection drops before the response arrives, the worker times out, the orchestrator retries. The customer is charged twice, and a Rust rewrite would not have prevented it.

Rust's ownership model removes use-after-free bugs and data races in safe code. It can't know whether a remote API finished an operation before the network failed. That takes durable state, idempotency and a recovery protocol that separates safe retries (a read-only search) from operations that need reconciliation (a payment).

Raw speed is a weak argument too. In an illustrative run of 4 model calls at about 800 ms, 6 tool calls at about 150 ms and 100 ms of orchestration, removing orchestration completely saves about 2.4%.

Where Rust earns its place is concurrency: how many agent sessions one worker sustains in a fixed memory budget at acceptable tail latency. Memory safety, concurrency correctness, distributed execution correctness.…