OptionaldraftOpen the pane editing a NEW, uncommitted item seeded with these properties, rather than on its list.
The pane mints the draft itself (anchored to the current selection, like its own add button): this is the feature's properties shape, not a model object, so it survives being handed across a workbook the caller does not hold.
Nothing is written until the user saves — which is the point of seeding a draft rather than adding a rule and opening the pane on top of it.
OptionaleditOpen the pane editing this EXISTING item — precisely what the item's own card edit does — rather than on its list. What an "Edit…" reaching the pane from elsewhere (the name box's menu) asks for.
OptionalinsertOpen the pane on a NEW, uncommitted item — precisely what its own add button mints — rather than on its list. What a "New Rule…" command asks for.
The same request as draft, with nothing to seed; a draft wins when both are given.
Ignored by a pane whose list is read-only, which shows no add button either.
The activation argument the built-in list panes (conditional formats, data validations, protected ranges) understand.
Remarks
Threaded from a command through
activateTaskPane(key, { args })— seeItemsDescriptor.createSeededDraftin@sheetxl/studio-muifor the receiving end.