In RF-12261, we have discussed necessity to duplicate information about description, to be able to retrieve description from shared attribute interfaces (like CoreProps in richfaces-ui-commons-ui package).

Once solution could be adding one additional build step, which would use the comment on the interface and copy it to the @Description annotation inside @JsfComponent annotation - this would allow to retrieve description from compiled packages.

See the linked RF-12261 and IRC log for more details