Versioning is a way to handle with changes on the current behavior of your API, that are incompatible with it.

Incompatible changes on your API can break or may require many changes for your API consumers.

What may be considered incompatible changes may vary from project to project. But a good common sense is removal of a non-optional field or alteration of an existing field on an endpoint. So, you must instruct the API consumers to handle additional fields they do not expect, and/or ignore them.

Add a version id after your domain. E.g.: https://example.com/v0

Make clear your API rate limits