Function scopes_for_service 

pub fn scopes_for_service(service: &str) -> Option<Vec<String>>

Every scope one service’s methods declare for grr auth login --service. The index is the same source the command tree and grr api describe read, so the set matches exactly what that service can be asked to do — and stays far below the size at which Google’s consent screen stops submitting. None when the index has no such service.