There are a few upcoming breaking changes in the Wikibase API.

* The items id as exposed to the outer world is now a numeric id. This will be prefixed with a letter and this letter will be used internally during lookup. Do not hardcode interpretation of this letter as it can be configured, but once configured it will be type-specific for the type of entity. https://bugzilla.wikimedia.org/show_bug.cgi?id=40381

* The encapsulating "items"/"item" in the reply will be replaced by "entities"/"entity" and it will be a new type-field in each entity. This field will have an identifier that says which kind of entity is in there. https://bugzilla.wikimedia.org/show_bug.cgi?id=40407 https://bugzilla.wikimedia.org/show_bug.cgi?id=40408

John Erling Blad