W3Cd

W3Cd, short for Web Content Descriptor, is a proposed open standard intended to standardize metadata descriptions of web content to improve interoperability, accessibility, and automated processing across platforms. Developed by a cross-industry community including browser vendors, content platforms, and accessibility groups, W3Cd seeks to complement existing schema formats by providing a focused, lightweight descriptor.

The specification defines a compact, machine-readable metadata block that can be embedded in HTML via a script tag with type="application/w3cd+json" or served as a separate JSON file linked from the document. The approach emphasizes ease of use for developers and predictable interpretation by tools, browsers, and accessibility services.

Its core metadata covers title, content type, language, and accessibility flags. Additional modules describe media characteristics (duration, dimensions, codecs) and provenance (creator, license, source). The standard also outlines validation rules and a registry to ensure consistent terminology and interoperability across implementations.

Implementation and status: As of its current draft, W3Cd is not widely implemented. Several content management systems and static site generators have experimental support, and a reference validator and registry are in development. The effort emphasizes compatibility with prevailing web technologies while aiming to remain lightweight and forward-compatible.

Reception and outlook: The proposal faces scrutiny for potential overlap with JSON-LD and Schema.org, but proponents argue it provides a lean, processing-friendly layer optimized for runtime use and accessibility tooling. W3Cd is intended as a community-driven proposal rather than a finalized specification, with ongoing discussion in standardization forums. See also: W3C, JSON-LD, Schema.org, Accessibility.