Muster

Muster is a macOS menu bar app that notifies users when AI coding agents need input and lets them answer or switch sessions instantly.

Muster is a macOS menu bar utility designed for developers running AI coding assistants like Claude Code, Codex, and Cursor. It monitors active sessions from the past three hours, alerts the user when an agent requires approval or input, and allows direct responses via keyboard shortcuts without leaving the current editor. The app displays detailed prompts, commands, and cost estimates locally, communicating with agents over localhost. It operates natively as a lightweight AppKit app with no external accounts or analytics. Supported interactions include local and remote SSH sessions, with open-source code under the MIT license.

Muster at a glance

Best for: Software engineer
Runs on: macOS
Pricing: Free
Released: October 2026
Category: AI coding tool
Website: agentmuster.app

Key features

Menu bar notification for waiting AI sessions
Instant command approval or denial with keyboard shortcuts
Session switcher accessed via Option-Tab
Localhost communication without external data transmission
Support for local and remote SSH sessions
Token usage and API cost estimation
Raycast and Alfred URL scheme integration

Use it for

Approving or denying AI agent commands instantly
Switching between multiple active coding sessions
Reviewing agent prompts and file edits before answering
Tracking token costs across AI sessions

Alternatives to Muster

Quotio — It unifies multiple AI provider accounts and tracks quotas in one dashboard.
barn — Monitors multiple AI coding agents on your Mac and jumps to the exact tab when needed.
Coucou — It provides open-source, real-time agent monitoring and approvals directly from the screen notch.
AgentDock — Manages multiple coding agents from one screen-edge inbox without switching tabs.
AG-UI — Standardizes agent-user interactions and generative UI for applications.
Lobster — Runs AI coding agents in isolated worktrees and nudges you only for human reviews.
CodexBar — See Codex, Claude, Cursor and 86 other limits in the menu bar
agterm — It organizes sessions into named workspaces and includes a local control API.
Maestro — Run multiple AI coding agents in parallel with automated workflows and mobile control.
Bama — Rebuilds any macOS app and automates the entire development process.
cmux — It features vertical tabs, notification rings, and split panes for AI coding.
Jango — Test multi-user workflows and interactive apps with autonomous AI participants.

All Muster alternatives