CodexIsland: AI usage limits in the MacBook notch

What CodexIsland shows and who wants it

CodexIsland is a native macOS app that turns the MacBook notch into a Dynamic-Island-style live view of your AI usage limits. It sits over the notch as a black pill, peeks on hover with the five-hour headline, and expands on click to show both Claude Code and Codex five-hour and weekly windows with reset timing, cost estimates from local logs, and a year-at-a-glance history. The audience is developers who run Claude Code and Codex heavily and keep bumping into rate windows, and who would rather glance at the notch than open two provider dashboards to see how much headroom is left. It is free, open source and local-first: it reads credentials that Claude Code, Claude Desktop and Codex have already written, then calls only the providers' own usage endpoints, so it is a viewer over data you already have.

How it reads usage without new credentials

The mechanism is deliberately minimal. CodexIsland does not ask you to log in again or hand it new keys; it reads the credentials already written by Claude Code or Claude Desktop and by Codex, then queries each provider's own usage endpoint to fetch the numbers it displays. That keeps it local-first, since the app is a presentation layer over the providers' data and your existing sessions, not a proxy that sits in the request path. On the display side, the compact pill is aligned to the physical notch and drawn with continuous squircle corners to match the hardware, and on a Mac without a notch it falls back to a configurable menu-bar pill. Clicking expands to three swipeable screens, Usage, Cost and Overview, so the same overlay covers current windows, spend estimates and longer-term history.

Installing it with Homebrew

CodexIsland is distributed as a Homebrew cask, which is the recommended install:

brew install --cask ericjypark/tap/codexisland

The first invocation auto-taps the maintainer's Homebrew tap. Existing installs auto-update through Sparkle, so you can open the app and check for updates on demand. The repository also ships a build.sh that compiles a universal binary with arm64 and x86_64 slices for building from source. One practical note the README is honest about: the app is unsigned, so on first launch macOS Gatekeeper will need you to allow it explicitly, and each release publishes a SHA-256 you can verify. That unsigned status is the main friction at install time, and it is the trade for a free, open-source app not going through Apple's paid signing and notarization by default.

Where a local-first usage viewer has limits

The limitations are the honest kind. CodexIsland is unsigned, so you accept the Gatekeeper step and should verify the published checksum, which is a reasonable ask but a step nonetheless. It is macOS-only and notch-oriented, with a menu-bar fallback for other displays, so it is not a cross-platform dashboard. It depends on credentials that Claude Code or Codex have already written, which means it only works once those tools are set up and logged in, and it depends on the providers' usage endpoints, so a change on their side can affect what it can show. The cost figures are estimates derived from local logs rather than authoritative billing, so treat them as a running approximation of spend, not an invoice. None of these break the core use, but they set expectations.

CodexIsland versus checking each provider's dashboard

The alternative is what most people do already: open each provider's own dashboard or usage page when you want to know how close you are to a limit. That is authoritative and needs no extra software, but it is two places to check, it does not live in front of you, and it does not fold both providers into one glance. CodexIsland's difference is that it unifies Claude Code and Codex five-hour and weekly windows in a single always-present overlay, with reset timing and a local cost estimate, so the information is ambient rather than something you go and fetch. The cost is running an unsigned third-party app that reads your local credentials. If you rarely hit limits, the dashboards are enough; if you juggle both providers and keep hitting windows, an always-visible unified view is exactly what this provides.

MIT license and release cadence

CodexIsland is MIT-licensed, so it is freely reusable, and it is written in Swift as a native macOS app rather than a web wrapper. The last push was on 2026-09-13, with version 0.2.5 from 2026-09-11 adding shareable usage cards, a 30-day range and usage-history retention, so it is under active development at an early version. Because it auto-updates through Sparkle, staying current is low effort once installed. Weigh the unsigned status as the main adoption cost, verify the release checksum on first install, and remember the numbers it shows are the providers' own usage figures plus local cost estimates, which makes it a convenience layer over data you already own rather than a new source of truth.

Editorial conclusion

Install CodexIsland if you run Claude Code and Codex on a Mac, keep hitting usage windows, and want both providers' five-hour and weekly limits visible in the notch instead of checking two dashboards. Do not expect it on other platforms, and accept that it is unsigned, so you will clear Gatekeeper and should verify the release checksum. Install it with brew install --cask ericjypark/tap/codexisland, and treat its cost figures as local estimates rather than authoritative billing.

Frequently asked questions

Official sources

1. ericjypark/codex-island on GitHub
2. License: MIT
3. Project website
4. README
5. Releases