Good Article. Two suggestions

I would make the attribute appear in the same code window as the method. At first it looks confusing because you have

<Microsoft.SqlServer.Server.SqlProcedure()> _

That ends in a continuation character that goes nowhere.

Then maybe a little more explanation as to why this attribute is needed.

Represents an abstraction of the caller's context, which provides access to the SqlPipe, SqlTriggerContext, and WindowsIdentity objects.

or

The SqlContext object can be used to obtain the trigger context (for code executing in a trigger) and the pipe object (when available, such as in stored procedures).

Definitions are taken from the MSDN.