Semantic HTML content

Weelkit publishes a sanitized semantic HTML fragment in contentHtml. It is not a complete HTML document and it is not Markdown. The versioned semantic catalog it follows is published as canonical-semantic-catalog.v3.json.

Supported content

The launch vocabulary includes paragraphs, headings, emphasis and strong text, links, lists, line breaks, quotations, code blocks, tables, figures and images, audio, video, and safe source elements. Images use one shared semantic type for inline, cover, and Open Graph usage profiles. Image properties can include asset identity, URL, alternative text, title, caption, dimensions, and MIME type when the active contract enables them. Image description is a distinct metadata property and is preserved only where the destination supports it. A quotation keeps its source URL in the standard cite attribute and visible attribution in a child <footer>. These are different values: provider serializers may transform the visible footer to an equivalent native citation element, but must not collapse it into the source URL. Scripts, event-handler attributes, unsafe URL schemes, arbitrary styles, unrestricted iframes, and unknown elements or properties are rejected. A destination may serialize a supported semantic value natively, as a structured value. If the destination cannot preserve it, the send stops with an explicit unsupported-content reason before anything is written.

Example

{
  "title": "A canonical article",
  "contentHtml": "<h2>Overview</h2><p>Weelkit keeps <strong>meaning</strong> separate from provider markup.</p><blockquote><p>One body, one contract.</p></blockquote>",
  "metaTitle": "A canonical article",
  "metaDescription": "A semantic HTML article fragment."
}

Use contentHtml for webhook and Custom API payloads. Weelkit never sends a parallel contentMarkdown field.

Article size

The saved body supports up to 8,192 semantic HTML elements and 8 MiB of UTF-8 HTML. Inline elements count too, so this is not a paragraph limit. Nesting is limited to 32 levels. An article over a limit stays Not saved; shorten it before sending.

Provider behavior

Each destination stores the content in its own native form. See How each destination behaves for details.

Destination	Body representation	Media and structured values
Ghost	Canonical HTML preserved in an HTML card	Mapped feature-image and metadata fields are separate; inline images keep their source URLs.
Self-hosted WordPress	WordPress blocks and post fields	Images are uploaded to the media library with their metadata through the Weelkit Plugin.
WordPress.com	WordPress blocks on the chosen site	Media and fields come from that site, separately from self-hosted WordPress.
Sanity	Schema-native Portable Text, with a declared HTML object for otherwise unsupported blocks	Native fields/assets require the discovered schema; HTML objects need a matching website renderer. See Sanity setup.
Custom API	Semantic HTML or structured fields, as the manifest declares	Fields and operations outside the manifest are rejected. Media isn’t uploaded: images must be publicly reachable URLs.
API webhook	Versioned signed canonical HTML envelope	Delivery is durable, idempotent, retried, and receipt-driven.

A valid credential doesn’t by itself make a destination ready: the mapping must be saved and a test draft verified first.

​Supported content

​Example

​Article size

​Provider behavior

Supported content

Example

Article size

Provider behavior