Install the Model Router · Her Frontier Build Lab

1Copy this line, paste it into your terminal

$ curl -fsSL https://model-router.herfrontier.workers.dev/install.sh | bash

Press return. It installs the four helpers and the rule into your Claude Code setup, then tells you exactly what it did.

You need: Claude Code, on a Mac or Linux terminal. On Windows, use the by-hand steps below.

What it does, in plain terms. The installer is a short script you can read before you run it. It never deletes anything. If a file already exists it saves a copy first. It adds one line to your settings so the rule is used every session, and it prints every change to the screen. Read the script first if you like.

2Prefer a download?

Grab the whole kit as a folder, then move the files in yourself. Nothing runs automatically.

Download the kit (.zip)

Show me the by-hand steps

Unzip it, then in your terminal:

mkdir -p ~/.claude/agents
cp agents/*.md ~/.claude/agents/
cp MODEL_ROUTING.md ~/.claude/MODEL_ROUTING.md

Then add one line to ~/.claude/CLAUDE.md:

Before any substantial task, choose the model and
effort using ~/.claude/MODEL_ROUTING.md.

3Check it worked

Restart Claude Code, then run this to see the four helpers sitting in place:

ls ~/.claude/agents

You should see writer, builder, analyst and fast-worker. That is it. From now on your assistant matches the tool to the task on its own, and you can ask it to use a helper by name any time.

Make it yours

Two edits worth two minutes.

Your privacy rule. Open ~/.claude/MODEL_ROUTING.md and set what counts as private for you. That rule sits above all the others, so your sensitive work never leaves your own machine.
Your voice. Open ~/.claude/agents/writer.md and describe how you actually sound, so the writer speaks like you and not like a chatbot.

What is inside

README.md
install and customise guide› MODEL_ROUTING.md
the routing rule (two spots to make yours)› writer
creative and voice work› builder
long, heavy, multi-step work› analyst
reasoning and checking› fast-worker
cheap, high-volume jobs›

How to remove it

rm ~/.claude/MODEL_ROUTING.md
rm ~/.claude/agents/{writer,builder,analyst,fast-worker}.md

Then delete the one routing line from ~/.claude/CLAUDE.md. Any file the installer replaced keeps a .bak copy next to it.