Kannu
Kannu vs menu bar agent monitors
The difference is where the status lives. Menu bar monitors — AgentBell, AgentBar, so-agentbar, AgentRadar and others — add an icon to a bar you scan deliberately. Kannu puts a traffic light in the notch: pixels that are already in your eyeline, so a colour change registers without you going looking for it.
The menu bar apps, fairly described
These are capable tools, and each has a distinct angle. Descriptions below come from each project's own public page:
- AgentBell — a menu bar icon that changes colour with agent state across Cursor, Claude Code and VS Code, with sound alerts per state transition and an optional animated desktop companion. Free tier covers Claude Code.
- AgentBar — tracks AI coding assistant usage in one place from the menu bar, with a stacked usage bar and desktop notifications.
- so-agentbar — monitors active Claude Code and Codex CLI sessions in real time, with tokens, costs and status per session.
- AgentRadar — monitors Claude Code, Gemini CLI, Codex and Aider with a status-changing icon, per-agent CPU, memory and uptime, and native notifications.
Why the notch instead
Three reasons, all about attention rather than features:
- The menu bar is contested space. Your eye visits it on purpose, next to a dozen other icons. The notch sits at the top-centre of the screen where your eye already rests — a light turning yellow there is noticed, not discovered.
- Panels, not dropdowns. Menu bar apps open a dropdown. Kannu's notch expands into full panels — sessions, quota and token spend, a focus timer, music — so the status display is also the workspace for acting on it.
- One light for many agents. Every session across Claude Code, Cursor, Codex, VS Code and Google Antigravity appears in one list, and the notch shows exactly one light, aggregated across all of them: yellow beats green, so an agent blocked on approval always outranks one that is working.
No notch is required: on Macs without one, and on external displays, Kannu runs as a floating Dynamic Island-style pill.
The short version
- Status location: notch (Kannu) vs menu bar icon (the rest).
- Interaction: full notch panels vs dropdown menus.
- Detection: Kannu registers hooks in each tool's own config — see how it works — rather than watching processes or logs.
- Tools tracked: Claude Code, Cursor, Codex, VS Code and Google Antigravity (Kannu); varies per competitor.
- Price and licence: Kannu is free and GPL-3.0, with source on GitHub; the others range from open source to freemium.