A new claudeDoc flag for artifacts and their durable subscriptions

What

Artifacts are documents Claude Code can publish. Pieces of a new Claude docs kind of artifact have appeared:

• The publish step takes a new claudeDoc setting, and the tracking of finished publishes checks claudeDocSlugs.
• A new function publishes with claudeDoc turned on. It reports whether a durable subscribe was armed, meaning an ongoing watch on the document was set up.
• A data format now accepts an optional claude_doc true-or-false value, which is ignored if it is malformed. It maps to claudeDoc being on.
• A failed subscription can now be reported with the reason claude_doc_not_admitted.

What produces or uses claude_doc was not traced, and no feature flag was found controlling it.

Why

This looks like groundwork for a kind of document that Claude Code can keep watching, where the watch can be refused. Since what produces or uses it was not traced, there may be nothing visible yet.