What connects to what

Give two structures and get the typed path between them — what contains what, what supplies what, what attaches to what — over the same relationship vocabulary the whole atlas uses.

Sixty-four types, and the list is closed

Relationships are typed, and the vocabulary is deliberately closed: part_of, has_part, supplies, innervates, attaches_to, drains and the rest. An invented type would traverse to nothing while every guard passed, so new types are added to the vocabulary, never to a caller.

A path is evidence, not a diagram

Every edge on a returned path carries the source that asserts it. A path with no evidence behind an edge does not render, which occasionally means the honest answer is that no recorded path exists.

Questions

Does this share an engine with atlas.leumas.tech?

Yes. Both doors read one relationship model; anatomy is one of its grains and this is the door that owns it.