Hi!
Your code was pretty close, you were just passing the wrong thing into setToolMode
. This code should work for you.
const tool = docViewer.getTool('AnnotationCreateRubberStamp');
tool.setStandardStamps(['SHAccepted']);
const annots = await tool.getStandardStampAnnotations();
tool.setRubberStamp(annots[0]);
instance.setToolMode('AnnotationCreateRubberStamp'); // sets it in the UI
Thanks,
Logan