maxStackSize exceeded causes an item to just be added to a different slot. Is this intended? about gdinv HOT 1 CLOSED

You meant maxStackSize? It only limits amount of items in a stack.

Basically the system works mostly in same way as in Minecraft game.
Each slot contains stack. Let's say you have inventory with 4 slots i.e. you can have four stacks.

Then you make arrow item:

{
    "id": "arrow",
    "attributes": {
        "maxStackSize": 16
    }
}

So you can carry four stacks of arrows, each stack/slot contains 16 of them. I.e. 64 arrows in total.

When you make item like this:

{
    "id": "diamond_sword",
    "attributes": {
        "maxStackSize": 1
    }
}

Then it means you can carry four stacks of swords, but each stack/slot contains only 1 sword. I.e. you can carry 4 of them in total.

There is no option to limit amount of stacks or total items with specified id in entire inventory. I didn't add such functionality to make system generic as possible.

from gdinv.