Thalia vs. using Muse in the terminal.
Thalia and the terminal are two ways to reach the same thing: Meta’s Muse Code CLI, under your own Muse account. This page is about when each one is the better fit. It is not an argument that you must choose.
This page describes Thalia 0.8.2.
The terminal is great at some things
A shell is hard to beat for quick one-offs, for scripting and automation, and for working on a remote machine over SSH. If you already live in a terminal, the CLI meets you there with nothing extra to open. Thalia does not replace that, and it does not try to run on a remote machine for you.
What Thalia adds
Thalia is a native Mac app that drives your installed Muse Code CLI. The CLI is still doing the agent work. Thalia adds screens and checks around it:
- Visual plan review and approval. A plan appears as a document with Discard, Request Changes and Approve and Build.
- Enforced read-only Plan mode. Choosing Plan restarts Muse read-only, and Thalia shows Plan only once that has happened. You can switch between Plan and Build while Muse is idle.
- Approvals that show the full command. Hidden characters are made visible, compound commands show Step X of N, and long commands and network addresses must be shown in full before you can allow them.
- Snapshot review and approval, with checks. When you approve a review, Thalia records that snapshot, and the approval is no longer valid if the files stop matching it. Your project’s checks run beside the diff.
- Checkpoints. Restore previews what it will change, saves your current files first, never changes files outside the project, and refuses to undo over newer edits.
- MCP connector management. Guided presets and custom connectors, with verification results and tool counts, and keys kept in the macOS Keychain.
- Voice. Talk hands-free or dictate into the composer.
- Home and notifications. Home shows approvals waiting, plans ready to review, failed checks and running work, and shows when a decision fails. Thalia can notify you when a routine finishes.
- Several projects at a glance. Each project is in the sidebar and each task has its own chat.
Side by side
| Muse in the terminal | Thalia | |
|---|---|---|
| Best for | Scripting, SSH sessions, quick one-offs and anyone who lives in a shell. | Working through a task visually, with plans, approvals and diffs on screen. |
| Muse CLI and account | Your installed CLI and your own Muse access. | The same CLI and the same account. Thalia runs your installed CLI. |
| Plans | You read the plan as text in your session. | Plan mode restarts Muse read-only and Thalia shows Plan only once that has happened. Approve to build, request changes or discard. |
| Command approvals | Prompts in your terminal session. | The whole command, with hidden characters made visible, before Allow is available. Step X of N for compound commands. |
| Reviewing changes | Your own tools, such as Git diff and your editor. | Review lists changes with text diffs, and approval is bound to a snapshot that stops being valid if the files change. |
| Checks | Run your own commands. | Save a verification command, run it beside the diff, and see pass or fail marked stale when files change. |
| Undo | Git, and whatever you set up yourself. | Checkpoints, with a preview before a restore writes anything. Not a backup. |
| MCP connectors | Configured outside the app. | Guided presets and custom connectors, with sign-in, tool counts and keys in the macOS Keychain. |
| Voice | Not part of a terminal session. | Talk and dictate, with replies read aloud. |
| Many projects at once | One session per terminal window or tab. | Projects in a sidebar, with Home showing what needs you across them. |
| Remote machines and scripting | Works anywhere you have a shell, including over SSH, and fits into scripts. | A Mac app for projects on your Mac. It is not a scripting tool. |
The terminal column describes what a shell naturally gives you. What the Muse CLI itself offers is up to Meta and the version you run, so check its own documentation.
You can use both
Thalia uses the same Muse Code CLI and the same Muse account as the terminal. Nothing about Thalia stops you from running muse in a shell on the same machine whenever that suits the job. Thalia also has a terminal for the project folder, so a quick command does not mean leaving the app.
Whichever you use, Muse’s output can be wrong. Review changes before you rely on them, and keep backups.
Requirements
Thalia needs a Mac with Apple Silicon running macOS 27, plus Meta’s Muse Code CLI signed in with your own Muse access. Review, checkpoints and worktrees need a Git repository. Thalia is free to use, and Meta sets any Muse subscription or usage charges. For more, see Thalia, a Mac app for Muse Code and the features page.