One Codex window per account on a Mac: Open, Show, never sign out

The official Codex app signs in one account at a time. CodexUse keeps every account in its own Codex window, with its own Codex home, auth, and history. You never sign out, and you never wonder which window is which account. There is one action per account: Open when no window is running, Show when one is.

Why one window per account

Codex keeps its login, config.toml, sessions, and logs in one home directory. Two windows on the same home share all of it. CodexUse gives each account its own home and starts exactly one Codex window on it. That is what makes the window a reliable stand-in for the account: if the window is in front, you are on that account, with that account’s settings, MCP servers, and history.

An account is one OpenAI account, signed in with the same OAuth as Codex CLI, or one custom-model account on an OpenAI-compatible provider. Both get their own window. They differ in who answers the model.

Open and Show

• Open starts the account’s Codex window. Every other account’s window keeps running and stays signed in. The status turns to Opening… for a few seconds, then Open.
• Show brings the running window to the front. It is the only action while a window is running, from the Accounts row, the ⌘K palette, the menu bar, and History.

The status word next to each account tells you which action you will get. Ready and Low mean Open. Open and Busy mean Show. Needs sign-in means the OpenAI login expired and you sign in again; the account and its config stay. Needs setup means a custom-model account is missing its provider or models.

Outside windows

If you start the Codex app from Finder or the Dock, that window is not on an account’s isolated home and CodexUse did not open it. The account shows an Outside CodexUse badge beside its status. CodexUse can see the window but does not control it. You have two options.

• Quit that window yourself and click Open.
• Turn on Take over outside windows in the Auto-roll menu. CodexUse then restarts an outside window under the right account when it needs to. Restarting loses unsaved work in that window, so CodexUse asks before the first take-over.

Headroom

Headroom is the percent of quota left that Codex reports per usage window: 5-hour, 7-day, and 30-day when your plan has one. CodexUse reads it after each account’s next Codex run and shows it under Quota left. Check usage reads it again now. When one window drops below your Warn below level, the account turns Low and, if you turned the toggle on, you get a Mac notification.

Refill timers

Use the refill time reported by Codex to decide whether to wait. Start refill timers automatically attempts a short background request after Auto-roll leaves an account. Start refill timers now attempts one for eligible OpenAI accounts, skipping excluded or known-exhausted accounts. These requests can use quota; they do not accelerate a refill or raise an account’s limit.

Auto-roll

Auto-roll moves the active account, the one the Codex CLI and the menu bar use next, along your priority order when headroom drops.

• Roll below X%: roll when the active account drops below this.
• Rejoin above Y%: reuse an account once it refills above this.
• Warn below Z%: send a Mac notification when an account drops below this.
• Priority order: each account’s detail has Include in auto-roll and arrows to move it earlier or later.
• Recent rolls: the log of what Auto-roll did and why.

Auto-roll has a confirm countdown that cancels a stale roll, and it never moves an open conversation between windows. Read Auto-roll guardrails for the failure cases.

Why never a second window

A second window on the same account would share the same Codex home, so both windows would read and write the same sessions and config at once. It would also share the same quota while looking like a separate account, which is the duplicate-account trap: two entries, one identity, no extra headroom. CodexUse avoids both by design. When two accounts resolve to the same OpenAI identity, the Accounts tab flags them, and Auto-roll skips the duplicate.

What this does not claim

• CodexUse does not create extra Codex quota. One window per account makes the quota you have visible.
• CodexUse does not move a conversation between accounts or merge cloud histories. History opens each task in its owning window.
• Taking over an outside window restarts it, and unsaved work in it is lost.
• Hosted ChatGPT features such as dictation need an OpenAI account. They do not work in a custom-model account’s window.
• Apple Silicon Mac only. The cross-platform CLI does not open Codex windows.