What
When Claude Code publishes an update to an Artifact (a page it creates and hosts for you), the upload can now carry two new optional pieces of information.
preconditions: conditions the server checks before accepting the upload. They are forwarded in the upload request when present.baseRebase: a label saying why the update was rebased onto a newer live version, with values such as 'forced', 'created_same_call', 'pins_off', 'no_listing', 'current', 'moved' and 'title_unusable'. The usage report for a publish now includes it asbase_rebase.- File-only updates can now also rebase onto the live version when only the favicon is being set. Before, rebasing happened only when no title, favicon, description, label or deadline was being set.
- Whether a listing's preconditions are adopted when working out the live version state (such as "no_listing" or "current") depends on a new server-controlled gate,
tengu_tidy_widget, together with whether preconditions were supplied. The gate falls back to true when no value is received; nothing has been read about it.
Why
These fields let the server tell when an Artifact has changed underneath an update, which should mean fewer spurious conflicts or silent overwrites when you republish. The gate gives Anthropic a way to switch the preconditions behaviour off remotely.
tengu_tidy_widget Not enough to sayNothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.
This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.281: on
These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.
Read once, for one account on one subscription tier, against v2.1.281. It isn't a statement about your account. What a flag value here can and cannot tell you
The finding does not say what a listing's preconditions are or what adopting them changes for the person publishing.
New in this build: tengu_tidy_widget