atc lets you run several coding agents at once in a single terminal pane and keep track of which are waiting on you.

claude, grok, and codex sessions all run in a background daemon, with a session list in front of them. There are no panes. One session fills the terminal, Ctrl-Space opens the list, a session that needs an answer turns red, and Tab takes you to it. Quit atc and the sessions keep running.

Install

bun add -g @zgeoff/atc

atc needs Bun and at least one of the claude, grok, or codex CLIs on your PATH. The agent picker lists the ones it finds.

Use

atc

The first run starts the daemon. Press n to spawn a session: pick an agent, pick a directory, give it a name, and type a first prompt if you have one. The session takes the whole screen and you work in it as you would in a plain terminal.

Ctrl-Space opens the session list over whatever you are attached to. Each row carries a state mark:

| Mark | State | | ---- | ------------------------------------- | | ● | needs you: a prompt or question waits | | ◐ | running | | ✓ | turn done | | ✗ | exited |

Sessions that need you sort to the top, so the one you want is nearly always first.

| Key | Action | | ------------ | -------------------------------------------- | | Ctrl-Space | open or close the list | | Tab | attach the session that needs you most | | Enter | attach the selected session | | / | filter by name or directory | | a | acknowledge a notification without attaching | | K | kill the selected session | | q | quit the client; sessions keep running | | ? | every other key |

The directory picker reads your zoxide list when zoxide is installed, and atc's own spawn history otherwise. Inside a Claude session your statusline gains a fleet segment, so ● 2 need you: auth-bug is visible without opening the list.

If the daemon dies, press R on the home screen and every session respawns from its transcript. After you upgrade atc, the status bar shows ⟳ update ready, and u restarts the daemon and restores the fleet when you are ready.

atc runs inside zellij or tmux. Give the pane locked mode so the leader key reaches atc.

Grok and Codex

Claude sessions report attention on their own: atc passes a generated settings file at spawn time and never edits your Claude config. Grok and Codex take a one-time hook install. atc prints the hooks and leaves the install to you:

# Grok
mkdir -p ~/.grok/hooks
atc grok-hooks > ~/.grok/hooks/atc-reporter.json

# Codex: merge the output into ~/.codex/hooks.json, then trust it once in the codex TUI
atc codex-hooks

The configuration guide covers both installs in detail.

Beyond the keyboard

• atc mcp exposes the fleet as MCP tools, so an agent can spawn, drive, and read other agents. A session spawned this way lists under the session that spawned it and is killed with it. Register it with claude mcp add --scope user atc -- atc mcp.
• atc events prints every fleet event as one NDJSON line. The same stream is on a unix socket, and config.json hooks run your own commands on events. The events guide covers all three.
• A Claude-compatible backend runs as its own agent in the same fleet. The gateways section covers the setup.

Configuration

atc creates ~/.config/atc/config.json on first run. The configuration guide covers every field: agent binaries and arguments, the leader key, gateways, and hooks.

Documentation

docs/ covers the architecture, the daemon, and the wire protocol.