hertta-site/v1 is Hertta's only authoring format: a content-first, normalized multi-file source tree. AI focuses on content and structure; presentation (theme, layout mechanics, CSS) is handled separately. It is not one JSON page document and not unrestricted YAML.
Two page formats live inside a site: YAML for rich, sectioned pages (landing pages, pricing, features) and Markdown for content-dominant pages (blog posts, documentation).
The platform-owned SITE_FORMAT_V1 registry in integration/generator/registry.ts is the executable source of truth for themes, components, properties, limits, routes, examples, and hash framing. Call site.format to get the same description live rather than trusting a static copy of this doc — the registry is what actually validates.
site.format also returns a model-facing authoring guide: an ordered workflow, page-mode and site-shell decisions, an exhaustive component guide with source fragments, composition recipes, quality and truthfulness ch