atc-bridge

<div align="center"> <picture> <source media="(prefers-color-scheme: dark)" srcset="./docs/assets/atc-dark.png"> <img src="./docs/assets/atc-light.png" alt="atc" width="256"> </picture> <p> <a href="https://www.npmjs.com/package/@zgeoff/atc"><img src="https://img.shields.io/npm/v/%40zgeoff%2Fatc" alt="npm version"></a> <a href="./LICENSE"><img src="https://img.shields.io/badge/license-MIT-blue" alt="MIT license"></a> </p> <p> <a href="./docs/README.md">Documentation</a> • <a href="./docs/guides/configuration.md">Configuration</a> • <a href="./docs/architecture/overview.md">Architecture</a> </p> </div>

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.

<img src="./docs/assets/demo.gif" alt="atc: spawn a session, open the session list, jump back in" width="1100">

Install

Homebrew:

brew install zgeoff/tap/atc

Or download a binary:

curl -fsSL https://raw.githubusercontent.com/zgeoff/atc/main/install.sh | sh

Prebuilt binaries cover macOS and Linux, arm64 and x64. The install script puts atc in ~/.local/bin; set ATC_INSTALL_DIR to change that. Checksums are on the releases page.

From source, with Bun:

bun add -g @zgeoff/atc

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

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; on a host atc can destroy, a dead session asks once more before forgetting destroys the host | | q | quit the client; sessions keep running | | ? | every other key |

The directory picker lists the directory you ran atc from, atc's own spawn history, every project under the roots in config.json, and your zoxide list when zoxide is installed. A typed path such as ~/pro completes like a shell. 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. The bar shows ⟳ restarting daemon until the restart finishes. When the running daemon speaks another protocol version, atc asks before it restarts the daemon, since the restart ends every session the daemon hosts.

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. Each agent keeps its own MCP config, so register the server once per agent you run:

  claude mcp add --scope user atc -- atc mcp
  codex mcp add atc -- atc mcp
  grok mcp add atc -- atc mcp
  

  A Claude or Codex session that is already running loads the server only after it restarts. A running Grok session loads it when you press r in its /mcps list.

• atc mcp --http serves the same tools over HTTP behind OAuth, so a hosted assistant such as ChatGPT or Claude.ai can reach your sessions with the scopes you approve. Add each assistant with atc clients add, approve each connection with the code printed in the server's terminal, and list or revoke grants with atc grants. Remote MCP covers it.

• A Claude session takes messages from other tools. atc_session_message queues one, and the session reads it in a new turn, or inside the turn it is running. atc_message_get returns that turn's final output once the turn ends, and waits for the next status change when given waitMs. The protocol covers the details.

• 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.