Three levels,
derived, not declared.
Verand clusters your pages by meaning, then picks the page each cluster most links up to as its pillar. Silos are a second pass inside each pillar. Willowdale's 269 crawled pages come out as 8 pillars, 17 silos, 213 filed articles and 8 standalones. The clustering is arithmetic on the embeddings and the link graph the crawl already stored; no model votes on your structure.
Tip: expand a pillar and drag any article onto another pillar to reassign it, or onto Standalone articles to un-file it. Edits are yours and survive re-scans.