Wikilayer keeps one source of truth: a tree of markdown nodes. Two surfaces project that source: a browser for humans, an MCP API for agents. Both see the same content, each in the form most useful for them.
That single source is more than a strict tree. Cross-links between blocks (page:N, block:N) and the back-references they generate turn it into a graph wherever the topic deserves it, and both views render the same hierarchy and association from one store.