You request the details from the server, and the server pushes you the data. The server can block you from doing this, as retail do for many of their test items.
However, here is the code:
Code:
/script DEFAULT_CHAT_FRAME:AddMessage("\124cff71d5ff\124Hspell:50010\124h[BOTM - Jungle Brew - Jungle Madness Vision Effect]\124h\124r");
Some bits are more obvious than others. spell:50010 represents that the link is a spell of the ID 50010. The name follows. The first few numbers are the colour as a hex value.
You can get this code from WoWhead which can generate it, just click "link".