Mods Optimizer is a powerful Minecraft utility mod that helps you automatically clean up and organize your mods folder by:

• 🧹 Removing duplicate mod versions
• 🛠 Renaming or moving incompatible client-only mods from the server
• ⚙ Classifying mods into client-side, server-side, or both

Whether you're maintaining a personal modpack or a multiplayer server, Mods Optimizer helps ensure everything runs smoothly and cleanly.

Mods Optimizer scans all .jar files inside the mods folder and analyzes metadata from:

• mods.toml
• fabric.mod.json
• quilt.mod.json
• META-INF/MANIFEST.MF

Based on this data, it classifies mods as either:

• 🖥 Client-only
• 🌐 Server-only
• 🔁 Both (default)

If not enough metadata is available, the mod uses a built-in internal list of known mods to determine classification.

When used on a server, client-only mods will automatically be renamed to:

???.client

It also identifies older versions of mods and removes them based on version numbers and known patterns.

Many Minecraft mods:

• ❌ Don't clearly specify whether they run on client or server
• 🔢 Don't follow semantic versioning correctly
• ⚠ Cause issues when multiple versions exist in the same folder

This creates extra work for modpack creators and server owners, who have to manually:

• Verify mod compatibility
• Remove outdated files
• Keep mods organized and synchronized across client and server

Mods Optimizer solves this automatically — saving time, preventing crashes, and reducing frustration.

Yes! You can override or extend the classification system using the configuration file:

config/mods_optimizer/mods.toml

[Mods]
ding = "client"
physicsmod = "client"
mousetweaks = "client"
client_side_mod_id = "client"
rubidium = "client"
server_side_mod_id = "server"
eatinganimation = "client"

Available values:

• "client" → Loaded only on the client side
• "server" → Loaded only on the server side
• "default" → Loaded on both sides

To regenerate the internal mod list:

1. ❌ Delete the file:

   config/mods_optimizer/mods.toml
   

2. 🔁 Restart the game or server.

Mods Optimizer will then re-scan all installed mods and create a new configuration file.

The Adaptive Performance Tweaks (APT) module uses file name patterns only to classify mods.
That means:

• ❌ Mods with irregular names or non-standard version formats might be misclassified
• ❌ It can’t read mod metadata for accurate classification

In contrast, Mods Optimizer:

• ✅ Reads actual metadata from mods.toml, fabric.mod.json, quilt.mod.json, and MANIFEST.MF
• ✅ Works with mods regardless of their naming convention
• ✅ Is more reliable, accurate, and future-proof