The client side encryption spec says that the driver should automatically spawn mongocryptd when it gets a server selection timeout when attempting to run a command against it.

https://github.com/mongodb/specifications/blob/master/source/client-side-encryption/client-side-encryption.rst#managing-mongocryptd

In the C# driver we have observed that it can sometimes take mongocryptd longer than 1 second to spin up, resulting in a second non-recoverable server selection timeout.

The spec should state that when the driver automatically spawns mongocryptd it should verify that the process is up and running and accepting connections before attempting a second server selection against it.