Desktop

The desktop app is the host. Agents run on this machine. Start chatting right away.

Install

Grab the app from Download. Settings can install the CLI for you — that is the binary Manage gateway needs.

First launch

1. Spellbook shows the agents from the public ACP registry.
2. Select the ones you already use (Claude Code, Codex, Grok, Gemini, …).
3. Continue installs them and opens New session.

The first selected agent is already in the setup bar. Pick a folder, then send a prompt. Add or remove agents later from Manage agents in the command menu.

Custom agents

Anything that speaks ACP can be added as a custom agent: command, args, and env. Registry entries that only ship a binary download are skipped for now — npx and uvx work.

This machine as a host for others

Manage gateway starts spellbook gateway here. Phones and browsers pair with the QR or URI. Quitting the app does not stop a gateway you started as a service; Stop gateway does. See Pair a host.

Cloud is optional

Sign in from Account when you want a hosted sandbox in the same catalog. Local agents keep working either way. See Cloud.