The API developer is able to retrieve the executing user and the logged on user.

/// <summary>       
/// <para>Retrieves the current executing user</para>        
/// </summary>        
/// <returns>The executing user.</returns>        
User GetExecutingUser()

/// <summary>        
/// <para>Retrieves the current logged on user</para>        
/// </summary>        
/// <returns>The logged on user.</returns>        
User GetLoggedOnUser()