What does a mod's dependencies question mean — what does mod X need?

"Missing dependency" is one of the most common modded crash messages. It simply means a mod needs another mod to run — here's what that means and how to fix it.

What a dependency is

Many mods require a library/dependency mod to function — for example, Fabric API for Fabric mods, or a specific core lib for Forge mods. Without it, the mod can't load.

Fixing a missing dependency

1. Read the crash message — it names what's missing (e.g. "missing dependency" or "requires X").
2. Find that dependency on the mod's CurseForge/Modrinth page (it lists required dependencies).
3. Download the correct version for your loader and MC version.
4. Upload it into the mods folder (via the Mods tab, Files, or SFTP).
5. Restart and confirm it loads.

Tip: The mod's CurseForge/Modrinth page always lists its required dependencies — check it before installing to avoid a boot crash.

Frequently asked questions

What does "requires X" mean at boot? Mod X is a dependency your installed mod needs — install X (correct version) into the mods folder.

Where do I find what a mod needs? On the mod's CurseForge or Modrinth page, which lists required dependencies.