Stockkeeping

A filtered comparator reads one item type from the container it faces and sends an analogue signal to the redstone circuit behind it. Only items matching the filter slot are counted, so the reading tracks that one item instead of the whole inventory. It works with chests and other inventory-containing blocks, and with an inventory-containing minecart on a detector rail.

Because the comparator updates only when it receives a comparator update, it avoids checking the inventory every tick. A plain vanilla hopper inventory cannot be read this way, so the mod's blocks are the intended source for the reading. The block is placed facing the inventory and its orientation matters for the signal output.

Stockkeeping runs on the client and on the server, so both sides need it. It is published for Fabric and Quilt, for Minecraft 1.20.1 only, and its files are dated 2026-01-07. The mod depends on no other mod on the Modrinth page, and its source code and issue tracker are public. The mod is open source under the GNU Lesser General Public License v3.0 only.