SPEM — Pre-defined UML stereotypes to be used in UML use case diagrams.

5. Pre-defined UML stereotypes to be used in UML use case diagrams.
When using a use case diagram to show the relationships between
ProcessRoles and WorkDefinitions we may want to distinguish
between assist and perform. The <<assist>> and <<perform>>
stereotypes could be defined for this purpose in the SPEM spec.
When no stereotype is used, the specification should indicate what is
the default interpretation that applies (according to figure 12-2 the
default meaning is assistance).
In addition, to render in a more user-friendly way the semantics of an
association between a ProcessRole and a WorkProduct, we could add
a <<responsible>> stereotype.

Accept.