# Setting up a client machine (Prism Launcher)

One-time setup, per machine. After this, launching the instance keeps the mods
in sync forever — no further manual steps, ever.

Frey's machine is a **Windows PC**; that is the primary path below. macOS notes
follow at the end (his friend's machine may differ).

---

# Windows

Run these in **PowerShell**. Claude can do all of it.

## 1. Install Prism Launcher

```powershell
winget install PrismLauncher.PrismLauncher
```

Or download from https://prismlauncher.org/download/

Sign in with the Microsoft account that owns Minecraft (Prism asks on first
run). Let Prism download Java when it offers — it manages its own.

## 2. Create the instance

In Prism: **Add Instance** → **Custom**

- Name: `Frey's Modpack`
- Minecraft version: **1.21.1**
- Mod loader: **NeoForge**, version **21.1.250**

Create it, but don't launch it yet.

## 3. Drop in packwiz-installer

Right-click the instance → **Folder**. That opens the instance directory; go
into `.minecraft\` (create it if it isn't there yet — it appears on first
launch) and download the bootstrapper into it:

```powershell
cd "$env:APPDATA\PrismLauncher\instances\Frey's Modpack\.minecraft"
curl.exe -L -o packwiz-installer-bootstrap.jar https://github.com/packwiz/packwiz-installer-bootstrap/releases/latest/download/packwiz-installer-bootstrap.jar
```

If Prism was installed somewhere else, use the folder that **Folder** opened
rather than the path above.

## 4. Point it at the pack

Right-click the instance → **Edit** → **Settings** → **Custom commands** →
tick **Custom commands**, and put this in **Pre-launch command**:

```
"$INST_JAVA" -jar packwiz-installer-bootstrap.jar https://mcpack.valls.dev/pack.toml
```

Type it exactly, `$INST_JAVA` included — Prism substitutes that itself on
Windows just as it does elsewhere. It is not a PowerShell variable, so don't
replace it with a path.

## 5. Launch

Hit **Launch**. The first launch downloads every mod in the pack (a minute or
two), then Minecraft starts. Add the server under Multiplayer:

- Name: `Servidor de Frey`
- Address: `valls.dev`

---

# macOS

Same five steps; only these differ:

```bash
brew install --cask prismlauncher
```

Instance folder: right-click the instance → **Folder**, then `cd` into
`.minecraft` and

```bash
curl -LO https://github.com/packwiz/packwiz-installer-bootstrap/releases/latest/download/packwiz-installer-bootstrap.jar
```

The pre-launch command is identical.

---

# That's it

From now on, every launch re-reads https://mcpack.valls.dev/pack.toml and adds,
removes or updates mods to match the server. If the client ever looks out of
sync, quit and launch again.

## Troubleshooting

**"Failed to download" / launch aborts before Minecraft opens.**
The pre-launch hook couldn't reach the pack. Check
https://mcpack.valls.dev/pack.toml opens in a browser. If it doesn't, the pack
server is down — tell Dad.

**The pre-launch command seems to do nothing.**
Check "Custom commands" is actually ticked, and that
`packwiz-installer-bootstrap.jar` sits in the same folder as `options.txt`
(i.e. `.minecraft\`), not the instance root beside `instance.cfg`.

**Windows: the launch fails complaining about `$INST_JAVA`, or "cannot find the
file specified".**
Prism normally substitutes `$INST_JAVA` itself on every platform — this is the
form packwiz documents, with no Windows variant — but if this build doesn't,
try `%INST_JAVA%` instead, and failing that put the full path to Prism's own
java there. Right-click instance → **Edit** → **Settings** → **Java** shows the
path it uses. Everything after `-jar` stays the same.

**Minecraft opens but the server rejects the connection with a mod mismatch.**
The server hasn't restarted since the pack changed. Ask Claude to restart it.

**Client-only mods (Sodium, Xaero's maps) are missing on the server — that's
normal.** They're marked client-side in the pack on purpose.