Minecraft Bot, does this feature work?

Hi, I'm currently programming my Minecraft Bot (that's a mod I've written) and that's supposed to be a sell / buy bot (for items on Griefergames.net, Citybuild) that means there's a sign on it. "Beacon = 800" so they throw the Beacon in (in a hole with water that leads to the bot) and the players get the Bot automatically the amount of money. My question would be now how can one adjust that the bot automatically knows the "XYZ" the Beacon threw pure. And then from 4 sides (a person has something also, it should be simple, but I can't get it and find synonymous nothing about it)

(I use Eclipse with Forge)

I'm looking forward to answers.

Inventory check… PlayerPickupItemEvent and then just your code after a few checks in or I understand something wrong