// redirect to @CoGroup
Builder builder = new Builder(CoGroup.class, context);
builder.addAttribute(FlowBoundary.SHUFFLE);
builder.addAttribute(a.getObservationCount());
builder.addAttribute(annotation.inputBuffer());
builder.setDocumentation(a.getExecutableDocument());
builder.addInput(
a.getParameterDocument(0),
a.getParameterName(0),
a.getParameterType(0).getTypeArgument().getType(),