Run Codex in parallel — Tallos

What is Codex?

Codex is OpenAI's open-source coding agent that runs locally as a command-line program called codex. You give it a task; it reads your code, edits files and runs commands in your terminal. It signs in with a ChatGPT account or uses an OpenAI API key.

Tallos is a desktop agent development environment that runs the real Codex CLI — not a copy or a wrapper that replaces it — and adds isolated workspaces, a chat view, account management and review, so you can run many Codex sessions at once and keep them organized.

How do I set up Codex in Tallos?

Open Settings → Connections, install Codex from its card, sign in, then set it as your default agent. If codex is already installed, Tallos detects it on your PATH.

1. 1

   Install

   Click Install on the Codex card. Tallos shows the official command before running it: npm install -g @openai/codex or brew install --cask codex on macOS, and npm install -g @openai/codex on Windows (Node.js required).

2. 2

   Sign in

   Click Sign in to run codex login in a terminal. To use an API key instead, click Use API key: Tallos passes it once to codex login --with-api-key, which stores it in Codex's own settings. Tallos keeps no copy.

3. 3

   Make it the default

   In Settings → Agents, set Codex as the Default agent so it is pre-selected in every new workspace.

4. 4

   Start a task

   Add a repository, click + to create a workspace and describe the task. Tallos creates a git worktree on a new branch and launches codex there, with the active account.

The same flow works for every CLI on the Connections page — see agent connections.

How do I run several Codex sessions in parallel?

Open one workspace per task. Each workspace is its own git worktree with its own branch, files and terminals, so parallel Codex sessions never write to the same working directory.

• Isolated by default. Each session's installs, builds and test runs stay inside its worktree.
• One screen. Split panes to watch several sessions; the sidebar shows which are working, waiting on you or done.
• Subagents under their parent. When Codex spawns Task subagents, they appear as child rows under the parent session.
• Restart without losing the account. When Codex exits, the restart chip relaunches it with the same account.
• Resume later. Agent Session History lists past Codex sessions; Resume runs codex resume <id> in the right folder.

See parallel workspaces for how the isolation works, and run AI agents in parallel for when splitting work pays off.

Give Codex five workspaces instead of one terminal.

Get Tallos →

How do I switch between Codex accounts and track rate limits?

Use the account switcher. Tallos lists your Codex accounts under Settings → AI Provider Accounts, lets you label them (“personal”, “work”) and swaps the active one in one click — no re-login, no config edits.

• System default is the same Codex login a codex in your terminal uses.
• Extra accounts run in their own isolated homes, with settings mirrored from your ~/.codex/config.toml, so credentials never mix.
• New sessions follow the active account. Sessions already running keep theirs until you restart them.
• Rate limits in the status bar. Usage against each limit window, time to reset, and a warning chip at 80%. The readout follows the active account.

On Windows, Codex can run from your host install or from a WSL distro; add a WSL-hosted account from the account switcher.

How do I use Codex alongside Claude Code and other agents?

Run them in parallel on the same repository, or combine them in a squad: a leader agent plus members, where each slot picks its own agent, model and effort level.

• Codex builds, another agent reviews. The build-and-review squad loops between a builder and a reviewer until the reviewer approves.
• Codex as one of three attempts. In *3 attempts, pick the best*, Codex, Claude Code and Gemini CLI solve the same objective in separate worktrees and the leader recommends one.
• Codex as leader. It divides the objective, dispatches members and combines the results within your limits: 5 rounds and 4 members at once by default, up to 20 rounds and 12 members.

Nothing merges until you Accept the result. For a fair look at how the two most popular CLIs differ in approach, read Claude Code vs Codex.

Does Codex open in a chat view or a terminal?

In a chat view, by default. Tallos decodes the Codex transcript into readable messages, tool calls and question cards, while the Codex CLI keeps running underneath.

• View terminal / Back to chat switch between the chat and the raw Codex TUI at any time.
• The model pill changes the model directly (it sends /model <id>); a bare /model still opens Codex's own picker.
• Type / for Codex's slash commands and your skills; attach files and images to a message.
• Want the terminal every time? Set Settings → Agents → Agent View to Terminal.

More in native chat.

What does Tallos add to Codex?

Codex works the same inside Tallos as in your terminal. Tallos adds the environment around it.