The sitemap lists every page a logged-out visitor may open, below every public root. To find those roots it asked the mesh for nodeType:Space is:main limit:500 (and the same for store plugins and catalogs), then kept the results whose path had no /. That is a window applied before the filter: with more than 500 Space mains on the mesh — every course installed into a user's space is one, every store plugin copy is one — which top-level roots landed inside the first 500 was decided by the storage's order, and a public root that did not make the window vanished from the sitemap. Nothing errored; the sitemap just listed fewer URLs, which is exactly what made it invisible. Measured on memex.meshweaver.cloud with 13 Space mains, so the window had not been hit yet — this was fixed before it bit.

The query language already pushes a root filter down — namespace: with an empty value is namespace = '' on every backend, the same shape the home page's root leg uses — so the sitemap now asks for top-level mains only, with no cap: the population is bounded by the number of partitions, not by the number of mains. A test plants 520 non-root spaces ahead of one public root and asserts the root is published; on the old enumeration the sitemap came back empty.