Stack Manager

Configurable stack sizes (vanilla + mods)

A lightweight server-side mod that generates a config with all items (vanilla + modded) and lets you set the max stack size per item. Works in singleplayer (integrated server) and on dedicated servers.

Features

• Generates config/stackmanager_items.json with every registered item.
• Per-item stack limits you can edit at any time.
• Auto-adds new items from newly installed mods on startup/reload.
• Safe network cap = 99 to avoid protocol/NBT issues.
• Optional in-game commands (enabled when Fabric API is present).

Commands

(optional, require Fabric API)
/stackmanager reload — reload the config and append any missing items.

/stackmanager set — set a new limit (clamped to 99).

/stackmanager set default — restore the game/mod default (clamped to 99).

Without Fabric API the mod still works; edit the file and restart (or reload using your preferred method).

Config file

Path: config/stackmanager_items.json

{
  "formatVersion": 1,
  "items": {
    "minecraft:acacia_button": 64,
    "minecraft:oak_planks": 99
  }
}

• Keys are full item IDs (namespace:item).
• Values are clamped to 1–99 at load time.

Handy editor shortcuts

(VS Code / most editors; Windows/Linux = Ctrl, macOS = Cmd unless noted)

Format document:

Shift+Alt+F (Win/Linux) · Shift+Option+F (macOS)

• Find / Replace:
  Ctrl+F / Ctrl+H · Cmd+F / Cmd+Alt+F
  -Select next occurrence (multi-cursor):
  Ctrl+D · Cmd+D
• Go to line:
  Ctrl+G · Cmd+G
• Select word / line:
  Ctrl+W (word) / Ctrl+L (line) · Option+Shift+→/← or Cmd+L (macOS)

Tips

• Keep IDs alphabetized for easier diffs.
• Use regex replace in Ctrl+H to mass-edit values.
• After editing, run /stackmanager reload (if commands available) or restart the world/server to apply changes.

Compatibility & limits

• The mod enforces limits on the server; clients don’t need the mod (unless other mods require it).
• Items with different NBT (custom names, enchantments, damage, etc.) never stack, by vanilla rules.
• Most vanilla and modded GUIs respect these limits. If a specific mod screen still caps at 64/99, report it—small per-screen patches are possible.
• Values above 99 are intentionally reduced to 99 to keep networking stable.

Requirements

Fabric API: optional but recommended for better experience (enables /stackmanager commands and smoother reloading).

Recommended usage

• Install Fabric API (recommended, not required) to use in-game commands and improve quality of life.
• Edit values directly in the config file before starting a world/server. Command-based changes—especially without Fabric API—can be cumbersome and may require restarts or extra steps.

Ideas for using the mod

• Potions:
  Easier: set potions to 16 or 32 per slot

minecraft:potion: 16
minecraft:splash_potion: 16
minecraft:lingering_potion: 8–16

Benefit: fewer inventory trips during raids, mining, and boss fights.

Note: Potions carry NBT (effect type). Only identical potions stack.

Other quick ideas

• Builder / mega-projects (QoL):
• Blocks (stone, planks, glass, terracotta) 99; food 64–99; firework_rocket 64–99.
• Exploration / Elytra:
  Rockets 16 (harder) or 64–99 (easier); Ender Pearls 16–32 (easier) or 8 (harder).
• Combat / PvE:
  arrow 99; snowballs/eggs 64–99 for events/minigames.
• Economy / survival challenge:
  Ores/ingots 16; ore blocks 8; pearls/snowballs 8 to curb spam

FAQ

• How do I find an item ID?

Enable advanced tooltips with F3 + H, then hover the item: you’ll see namespace:item.

• Can I set 9999?

No. For network safety the effective cap is 99.

• Singleplayer or server?

Both. In singleplayer, drop the mod into mods/. On a dedicated server, only the server needs the mod.