What MCPitanLibarch Does and Why You Need It
A Library Mod, Not a Gameplay Mod
MCPitanLibarch is a library mod built around the Architecture API. On its own it adds nothing you can see or use in-game — no new blocks, items, or mobs. Its entire purpose is to provide shared code that other mods depend on.
If you installed it expecting new content, you will be disappointed. The mod exists purely as a foundation.
Why It Appears in Your Mod List
Some of Pitan's mods require MCPitanLibarch to be present in order to function. Without it, those mods will fail to load or crash. This is why the library often shows up alongside other mods rather than being downloaded on its own.
What You Need to Do
Treat MCPitanLibarch like any other dependency. Install it in your mods folder when another mod lists it as required, and leave it alone otherwise. You do not need to configure it or interact with it in any way. If a mod you want specifies this library as a requirement, simply having it installed is enough.