They have a governance panel for all AWS services that approves design docs and API contracts (at least this is what I was told by an old manager who worked on AWS back in the day).
there's also a significant amount of automation in place these days to sass you in the right direction, i.e.
* focusing on resources and operations on resources
* using consistent and expected naming schemes, pluralization, etc.
it also helps that the sdks and clis are very raw wrappers around this, such that if you know what it looks like in the sdk then it will look similar in the cli.