Constant FACADE_TREE 

const FACADE_TREE: &str = "atune";

The crate whose rustdoc subtree the reverse check covers.

The facade, and only the facade. The map’s Rust half is the facade’s own re-export lists, so it is the one crate whose coverage is answerable: demanding that every page of atune_core’s tree be claimed would demand a map of a crate the guide deliberately does not document symbol by symbol (§8: each API reference stays in its idiomatic home).