The Tahuti sketch recognition agent recognizes several drawn shapes.  The system recognizes UML class diagram symbols including a general class, drawn as a square, an interface class, drawn as a circle, an interface association, drawn as a line connecting a general class to an interface class, a dependency association, drawn as an arrow with an open arrow head, an inheritance association, drawn as an arrow with a triangle arrow head, and an aggregations association drawn as an arrow with a diamond arrow head.
	The system was built for software design within the Intelligent Room of the MIT AI Lab.  Intelligent Room applications are built from agent technology,  run on the Metaglue agent infrastructure, and frequently have speech interfaces to them.  Thus, we added two additional symbols to aid in describing agent-based software, an agent class, drawn by a double-edged rectangle, and a speech grammar, drawn by a triangle or pentagon.