What element in Magicdraw is equivalent of a controller?

I have to create a sequence diagram using Magicdraw and I need to add controller elements.

• Entities stand for real world things.
• Interfaces aka boundaries views/models
• Controllers controllers in actual code but what kind of element they are in Magicdraw... no idea.

As far as I know, there is a robustness diagram in Magicdraw. Depending on your version it should be on some sort of "Custom diagrams" or "Analysis diagrams" submenu. There you can use the palette to create Boundaries/Entities/Controllers.

Anyway, internally, these elements are just plain old classes with appropriate stereotypes (so you might reach the same result without using the custom diagram by creating classes and applying the stereotypes manually).