Example:

Code (Skript):

1. command /xxxx:
2.     trigger:
3.         open chest with 3 rows named "test" to player
4.         formatSlot(player's current inventory, 10, 1, (diamond named "&b&lDIAMOND"), "broadcast ""Skript is awesome!""")

Requires:
- SkStuff
- SkQuery


Code:

Code (Skript):

1. function formatSlot(inv: inventory, slot: integer, amount: integer, item: item, action: text = ""):
2.     if {cfs.p} isn't set:
3.         set {cfs.p} to random 4 char string from `a-zA-Z0-9`
4.  
5.     set slot {_slot} of {_inv} to {_amount} of {_item}
6.     if {_action} isn't "":
7.         replace all """" in {_action} with "|q?%{-cfs.p}%|"
8.         replace all "," in {_action} with "|c?%{-cfs.p}%|"
9.         replace all "%%" in {_action} with "|p?%{-cfs.p}%|"
10.        
11.         add "{SkriptClickEvent:%{_action}%}" to nbt of slot {_slot} of {_inv}
12.  
13. on drop:
14.     "%nbt of event-item%" contains "SkriptClickEvent"
15.     cancel event
16. on inventory click:
17.     set {_} to tag "SkriptClickEvent" of (nbt of slot clicked slot of player's current inventory)
18.     {_} is set
19.     cancel event
20.     replace all "|q?%{-cfs.p}%|" in {_} with """"
21.     replace all "|c?%{-cfs.p}%|" in {_} with ","
22.     replace all "|p?%{-cfs.p}%|" in {_} with "%%"
23.     evaluate "%{_}%"