The 2.0 specification states that scope annotations with attributes result in non-portable behavior:
https://docs.jboss.org/cdi/spec/2.0/cdi-spec.html#defining_new_scope_type

At the same time Java EE standards like JSF use attributes on some of their scope annotations.:http://docs.oracle.com/javaee/7/api/javax/faces/flow/FlowScoped.html

There are use cases of applications that have a well defined structure, but the user must specify multiple copies of that structure. One can imagine a server application that must handle multiple endpoints, so the user must have the means to create multiple copies of a request processing pipeline. E.g. @RequestScoped("login"), @RequestScoped("shopping-card").

Ideally CDI should use annotation instances, rather than annotation classes to select contexts.
http://docs.jboss.org/cdi/api/2.0/javax/enterprise/inject/spi/BeanAttributes.html#getScope--
http://docs.jboss.org/cdi/api/2.0/javax/enterprise/inject/spi/BeanManager.html#getContext-java.lang.Class-
http://docs.jboss.org/cdi/api/2.0/javax/enterprise/context/spi/Context.html#getScope--

If this is not possible at least BeanAttributes can have a convenience method to get the scope annotation instance, and the specification should explicitly allow the use of attributes on scope annotations.