The VisualScript SDK in JavaScript is built into both SmartDraw and VisualScript if you use the built-in script editor.
There's no reason to download or install anything else.
You can explore all the classes and methods of the built-in JavaScript SDK in this guide.
If you need to create a REST endpoint or a SmartDraw extension hosted on your own servers, these software developer kits (SDKs) will help you generate
VSON markup.