CobSwap

CobSwap

CobSwap is a client-side Fabric mod that places cobwebs for you during combat. Hold a sword or axe, left-click a block next to your opponent, and it switches to your cobweb, places it, and switches back to your weapon. It uses normal slot switching and block placement, with an adjustable delay between steps.

No server-side install is needed.

Features

• One-click cobweb placement. Left-click a block while holding a sword or axe, and CobSwap handles the swap, place and swap-back.
• Combat-aware. It only triggers when a living entity (a player or a mob) is within about 3 blocks of the placement spot and the spot is empty. Everywhere else, mining works as normal.
• Normal attacks are untouched. CobSwap only reacts to left-clicks on blocks. Hitting a player or mob works exactly as in vanilla.
• Adjustable delay. The wait between steps defaults to 2 ticks (about 100 ms) and can be set from 0 to 10 ticks. You can change it live in-game, and it is saved to config/cobswap.json.
• On/off toggle. The mod starts OFF each time you launch the game, so it never fires unexpectedly. This also stops it from placing webs while you mine with a sword.
• Rebindable keys. Every keybind is listed under Options > Controls > Key Binds > CobSwap.
• Action-bar feedback. Toggling and delay changes show a short message above your hotbar.

How it works

When CobSwap is ON, all of these must be true:

1. You are holding a sword or axe in your main hand.
2. You left-click a block (not an entity).
3. The space next to the clicked face is empty.
4. A living entity is within about 3 blocks of that space.
5. A cobweb is in your hotbar (slots 1-9).

CobSwap then cancels the normal mining action, switches to your cobweb slot, waits for the delay, places the cobweb, waits again, and switches back to your original slot. If any condition fails, the click behaves as vanilla Minecraft would.

Default controls

Action · Key
Toggle CobSwap on/off · G
Increase delay (+1 tick) · ]
Decrease delay (-1 tick) · [

All of these can be rebound in the Controls menu.

Requirements

• Minecraft 1.21.11
• Fabric Loader 0.19.3 or newer
• Fabric API
• Java 21

Installation

1. Install Fabric Loader for Minecraft 1.21.11.
2. Put Fabric API and the CobSwap jar in your mods folder.
3. Launch with the Fabric profile and check your keys in Controls.

Important notice

CobSwap automates a repeated inventory action in combat. Many multiplayer servers prohibit macros or automation, and some anti-cheat systems flag fast inventory actions even when each one is a normal game action. Check the server's rules before using this mod. If a server is strict, raise the delay with the ] key. You use this mod at your own risk.