Modrinth

The modrinth plugin, from @opys/minecraft.

Mods from Modrinth, named by version.

modrinth({
  to: (file) => '${game_directory}/mods/' + file.filename,
  versions: [
    'JjCVwmVA', // an ID
    'https://modrinth.com/mod/lithium/version/N08Z8wog', // or the page's URL
  ],
});

Options

Option	What it does
versions	Version IDs, or version page URLs.
to	Where each file goes.
apiBase	A mirror of the Modrinth API.

to

Called once per file. Returns where that file is installed.

file.	Is
filename	The jar's name.
versionId	The version you named.
versionNumber	Its version string.
projectId	The mod's project.
size	Size in bytes.

Start the path with a variable such as ${game_directory}. It is filled in on the player's machine.

What it adds

Kind	What
Files	One per version you named.
Launch	None.
Variables	None.
Environment	None.

Each one below: what it is, and how it ends up in the manifest.

Files · one per version

The version's primary file, from Modrinth's CDN, pinned by the sha1 Modrinth publishes. path is what your to returned.

// opys.config.mjs
export default defineConfig({
  plugins: [
    fabric({ version: '1.21.1' }),
    java({ version: '21' }),
    modrinth({
      to: (file) => '${game_directory}/mods/' + file.filename,
      versions: ['JjCVwmVA'],
    }),
  ],
  manifest: {
    command: '@fabric.command',
    args: ['@fabric.jvmArgs', '@fabric.mainClass', '@fabric.gameArgs'],
    workdir: '${game_directory}',
  },
});

// in the manifest
{
  "path": "${game_directory}/mods/sodium-fabric-0.8.12-beta.2+mc1.21.1.jar",
  "source": { "url": "https://cdn.modrinth.com/data/AANobbMI/versions/JjCVwmVA/sodium-fabric-0.8.12-beta.2%2Bmc1.21.1.jar" },
  "size": 1573186,
  "integrity": { "sha1": "6c8b02b70540dd3330c7877277b35fabcf1c2c4b" }
}

No launch pieces and no variables. Mods do not change how the game starts.

Why by version and not by project: "Sodium" is a moving target. One version is one exact file.

A whole modpack

plugins: [
  modrinthModpack({ pack: 'xVcA1pSL' }),
  java({ version: '17' }),
],
manifest: {
  command: '@modrinthModpack.command',
  args: [
    '@modrinthModpack.jvmArgs',
    '@modrinthModpack.mainClass',
    '@modrinthModpack.gameArgs',
  ],
  workdir: '${game_directory}',
},

pack is a version ID, the version page's URL, or a direct .mrpack link.

It adds three things:

What	Why
The loader the pack asks for	A pack is Fabric, Forge, NeoForge or vanilla. You should not have to look.
Every client-side file	The pack's mods and resource packs.
The pack's overrides	Its configs, unpacked into ${game_directory}.

The launch pieces are the loader's, under the name modrinthModpack. So the launch line is the same whichever loader the pack uses.

loader: (spec) => … lets you set the loader up yourself, for example with a mirror. Quilt packs are not supported.

Good to know

• opys installs what you name. It does not check a mod against your loader or Minecraft version.
• A mod's dependencies are not added. List them.
• One to per plugin. For a second folder, add the plugin again and rename it: .as('resourcepacks').
• A modpack does not say which Java it wants. Add java.