A series, record or list message declares its shape instead of riding
DType.JSON, so a widget binds a shape rather than some JSON and a wrong
binding is refused before anything runs. A list declares its item type,
which is what keeps list[float] expressible for a pipeline.
On top of that: an agenda over a list, a notification over a record, and
a dashboard alert channel that publishes engine faults as one — so a
panel can show what went wrong without a flow wiring it by hand.
Also: only None means a node published nothing, a falsy value of the
wrong shape is now the named error it always should have been; and the
gauge's readout says its size is viewBox geometry rather than type scale.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>