Extraction and rendering

The program first fetches a page and extracts its available metadata into a PageInfo value. Supported groups include Open Graph, Twitter Cards, JSON-LD, App Links, HTML link relationships and selected site-specific information.

Different output styles render selected properties rather than changing the underlying extraction. The json style exposes structured fields; the Open Graph and Twitter styles focus on their respective families. This is why a field may be present in one style but omitted by design in another.

Lint rules and rule lists inspect the extracted result and report issues. The card commands use the same metadata to generate shareable images, while edit operates on local HTML documents.

For source-level details, see PageInfo on pkg.go.dev, the template files and lint rules. These are authoritative for exact fields and supported behaviour.