Seahelm

What is Seahelm

Seahelm is a macOS workspace designed for coordinating coding agents across multiple git worktrees and parallel tasks. It runs natively on macOS 14+ and is built with Swift and AppKit. The app centers on a single fleet view: each repository you add becomes a project, each worktree appears as a row, and each split-pane leaf holds one agent session.

Seahelm is not a traditional code editor and it is not a diff-first review tool. Instead, it focuses on orchestration: placing agents, tracking their state, and making it easy to see when a worktree needs a human. The desktop app uses the Ghostty engine to render terminals, and it keeps sessions persistent through zmx so the layout can survive a reboot.

Key features

• Worktree-centric fleet view: the app can group your fleet by repository, by status, by last activity, or expand it down to every individual pane.
• One agent per split pane: each leaf in a worktree’s binary split tree holds exactly one agent, which makes the layout predictable when several tools are active at once.
• Terminal rendering on Ghostty: Seahelm draws every terminal session on Ghostty rather than embedding a generic shell view.
• Persistent sessions with zmx: the app restores session state after relaunch, so panes reappear where you left them.
• Out-of-the-box agent CLI support: the site says twelve agent CLIs work without extra setup.
• Status tracking: the UI distinguishes between running sessions, idle sessions, and worktrees that need input.
• Token and quota readouts: Claude and Codex session logs are parsed into token and quota figures, with the status pill rotating through one readout at a time.
• Remote access option: a browser client called seahelm-web can be paired with an eight-digit code, and it opens a real terminal over a WebSocket connection.
• Suggestion surface called the Island: a top-of-screen pill opens when something is running, waiting, or broken, and it can show clickable agent suggestions.
• First Mate automation: an autonomous supervisor can take green-zone actions automatically and queue higher-risk actions for approval.

How to use it

1. Install Seahelm on a Mac running macOS 14 or later.
2. Add a git repository to create a project.
3. Let the app discover worktrees from git worktree list --porcelain, or open the fleet view to see existing rows.
4. Start or attach an agent in a split pane so each pane maps to one active session.
5. Use the roster controls to sort by repo, status, or recent movement when you need to focus on a subset of work.
6. Watch the Island and status indicators for tasks that are waiting on input, blocked, or finished.
7. Use the side panel for file tree browsing, code editing, Markdown preview, or git diff review without leaving the worktree.
8. If you relaunch or reboot, Seahelm restores the saved layout and session state.

For remote use, pair seahelm-web with the eight-digit code shown by the app. The browser client lists the fleet and can open a real terminal on a selected pane.

Who it is for

Seahelm is for developers who run several coding agents at once and need a structured way to keep them separated. It is a fit for:

• engineers using git worktrees for parallel feature branches;
• teams or solo builders running Claude, Codex, Aider, or other supported agent CLIs;
• macOS users who want a native control surface instead of juggling multiple terminal windows;
• people who want status-aware agent management rather than a single opaque terminal session.

It is especially useful when you need a direct view of which agent is busy, which one is idle, and which worktree needs a decision.

What to know before you use it

Seahelm is focused on orchestration, not full IDE replacement. It does not claim to be a general-purpose editor, and the site explicitly says there is no editor-diff ceremony at the center of the product. If you need a full code review workflow or a conventional editor-first environment, you may still want a separate tool.

A few other caveats are worth noting:

• The app is limited to macOS 14+.
• Remote browser access exists through seahelm-web, but the Telegram and email control paths are described as experimental.
• The site highlights Claude and Codex token/quota parsing, so other agent tools may not have the same depth of usage reporting.
• Seahelm can show and manage what the app can observe in its own session model, but it is not a substitute for checking the underlying repo state in Git or using the official agent CLI when you need source-of-truth behavior.
• Some automation is approval-gated by design, so higher-risk actions still require a human decision before they run.

If you are choosing a macOS workspace for coding agents, Seahelm is best when you want a persistent, status-aware terminal fleet rather than a single shell or a generic IDE. It helps you keep parallel development organized while still leaving the final source of truth in Git and the agent tools themselves.