To use the API effectively, a basic understanding of Javascript is required. In addition, familiarity with Three-dimensional Geometry and 3D Math library will certainly help.

A proper understanding of concepts in three dimensional co-ordinate geometry is required to build complex shapes using scripting.

Quick reminder: There is a difference between geometric entities and topological entities.

Line, Rectangle, Circle etc represent geometrical entities.

Edge or Wire represent topological entities. Every topological entity is associated with some geometry.

Path class is just a convenient wrapper for managing edges and wires. It represents neither a geometric entity nor a topological entity.

Refer to Using cadlib object page to undestand how to create shapes, edges, wires, faces etc and manipulate them to create more complex geometries.