Guild Wars 2

Recently I’ve seen people posting custom chat links in chat. Such as things like [s][w][a][g], with each letter inside the brackets linking an item and being a different color (based upon linked item quality). I’ve been trying to do the same thing but first thing’s first, quantities.
On the wiki it says that one byte of data stands in for the quantity. Here ([&AgHhdwAA]) is the code for Eternity which I am testing on. I have yet to be able to get this to output a quantity linking with Eternity, however other items with quantities have been output such as “7 sword”.
Secondly, is to find out how custom letters, such as above example, are able to link to an item. I’ve tried inserting strings (“[insert text here]”) and just about anything that could come to me this late at night. No luck as of yet. If anyone here understands the complicated nature of the chat link system an explanation would be very helpful.

Thanks in advance for any help received!