An hm:// URL is a name reference: how one schema points at another (hm://hyper.media/string). A name does not depend on content, so names can form cycles, which a CID cannot. That is what makes recursion expressible. Local filenames are the dev alias (string ⇄ hm://hyper.media/string). hyper.media is a name the SDK and the docs sync understand. The network does not resolve domains in hm:// URLs yet, so published documents carry the key of the space instead.

As a value type it is a reference to a Hypermedia document, held as an hm:// URL string. format: hm-url tells an editor to render it as a searchable reference that shows the target's title as a pill, instead of the raw URL. A target on the field names the schema the referenced document should be typed by: the search then offers documents whose effective attributes schema is that type or any extension of it, and a reference outside that set gets a warning, never a block.

This page describes the hm-url type, a value type of Hypermedia Schemas. Its formal schema is attached as the schemaDefinition in this document's metadata, so the app can show it and create values of this type.

See also

URLs: the full hm:// syntax.

References and naming: how schemas refer to each other.

url and ipfs-url: the other URL types.

metadata: attributesSchema and childAttributesSchema hold this type.