FAQ#

Is Modsmith a launcher?#

No. It is a Python library for building tools. It prepares the game files, and the official launcher starts the game.

Does it need a copy of Minecraft?#

It downloads game files from Mojang, as the launcher does. Players need to own the game to play it.

Do I need Java installed?#

No. Modsmith uses the official launcher’s runtimes, or downloads one from Mojang. It only needs Java to install Forge and NeoForge.

Do I need a CurseForge API key?#

Only to use CurseForge. Reading a CurseForge .zip works without one, but downloading its files needs a key. Modrinth needs no key.

Can I ship an API key inside my app?#

Anyone can extract a key from a distributed app, so check CurseForge’s terms and choose carefully. Tools that run on your own server can keep the key private.

Why can’t Modsmith download every CurseForge mod?#

Some authors do not allow third-party downloads. See Install CurseForge packs.

Can I install into `.minecraft` directly?#

Use a separate instance folder. A sync manages every file it installs, and it would mix a pack’s files with your other games.

Is it safe to call from several threads?#

Yes, and from several processes. A Session can be shared between threads, and locks keep installs out of each other’s files. A second sync of one instance raises LockedError at once, because it is usually a mistake. Installs that share a game directory or cache wait their turn, for up to ten minutes.

Does it work with servers?#

Instance.sync accepts side="server", which installs a server’s files. Installing a loader for a server is not supported yet.

Does it work with Bedrock Edition?#

No. Modsmith only works with Java Edition.

Is the API stable?#

Not yet. Modsmith is in alpha, so the API may change between releases. Changelog lists what changed.