First-class Muse CLI support — identity + presence badges

[marvtub]

What problem does this solve?

I run Muse Code (Meta's muse CLI, powered by Muse Spark) inside Supacode panes daily. Today it launches as a plain terminal command and is not a recognized agent, so a muse worktree gets a degraded experience versus Claude/Codex/Copilot worktrees:

• No presence badge — the pane never shows busy / awaiting input / idle, so I can't tell at a glance which worktrees need attention.
• No attention/notification flow — notified-worktree-to-top and the notification flows never fire for muse sessions.

Proposed solution

Recognize muse as a first-class harness for identity + presence badges, at parity with the other supported agents.

One wrinkle worth flagging: I checked Muse's side for a lifecycle-hook system matching the hook → OSC 3008 pattern Supacode uses for the other harnesses, and could not find one (no hook concept in its exported session schema or settings). So the Kimi-style hook installer may not transfer directly. Possible routes, in the author's preferred order:

1. If Muse gains hooks, install the managed hook block like the other harnesses.
2. Until then, process-based detection (the muse / muse-bin-* process owning the pane TTY) driving busy/idle, even without the awaiting-input state — still a large upgrade over no badge at all.

Happy to test builds and report back from daily muse usage.

Alternatives considered

• Keep launching muse as a plain command. Works, but yields no badge, no identity, no notifications — the exact degraded experience this solves.
• Switch those worktrees to Claude/Codex. Not acceptable: the work is Muse-specific.

Supacode version

0.10.8 (build 1785775286).

Environment

• macOS 26.x (Tahoe), Muse Code 1.3.0, muse on PATH at ~/.local/bin/muse
• muse runs in the pane's login shell like any other agent CLI; no wrapper or shim involved

Are you planning to build this yourself?

• I intend to open a pull request once this is approved and marked ready.

Before submitting

• I searched existing issues and this is not a duplicate. (First-class jcode harness support — identity + presence badges #815 covers jcode, Grok agent presence badges never appear on a fresh install #704 covered Grok; nothing covers Muse.)
• I understand feature pull requests are closed until the issue is marked ready.
• I agree to follow this project's Code of Conduct.

[github-actions]

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