AI Usage

AI Usage is a native macOS widget for people who burn through Claude Code and Codex sessions all day and want a glance, not a webpage, to tell them where they stand. Drop it into Notification Center and the ring on the left fills with your current Claude session, the ring on the right with your Codex five-hour window. The Large variant adds weekly all-models, Sonnet only, Claude Design, Codex weekly, and the rolling extra-usage spend against your monthly cap.

The numbers are real. Claude data comes from claude.ai/api/organizations/.../usage. Codex data comes from chatgpt.com/backend-api/codex/usage. There is no scraping, no shell-out to a CLI, no estimating from local jsonl. The host app does the network work every five minutes and writes the result into a JSON cache the widget reads on its next timeline refresh. If a request fails, the widget keeps showing the last good values and the local jsonl scan is used as a fallback so the rings never go blank.

Authentication for claude.ai was the interesting problem. There is no public token, so the host app opens claude.ai/login inside a WKWebView, observes the WKHTTPCookieStore, and grabs the sessionKey cookie the moment login completes. The cookie lives in the macOS Keychain. No copy-pasting cURL out of devtools, no manual session refresh, and Google SSO works in the embedded view the way it does in Safari. Codex is even simpler. After codex login on the terminal, the bearer token sits in ~/.codex/auth.json and the app reads it directly. Zero setup.

The non-obvious technical challenge was sharing data between the unsandboxed host app and the sandboxed widget extension. App Groups would have been the textbook answer, but a wildcard Developer ID provisioning profile strips the App Groups entitlement, so the widget cannot read the shared container. The workaround is to skip App Groups entirely. The host writes the cache directly into the widget extension is own sandbox container at ~/Library/Containers/<widget-bundle-id>/Data/Library/Application Support/, and the widget reads its own files. No entitlement gymnastics, works on a personal Developer ID with no profile dance.

The setup screen is a single card with two rows. Each row shows a status dot, a "Connected / Not signed in / Not detected" label, the plan tier, and a contextual action button. If Claude Code is not installed, the row collapses to a discreet "Install →" link. Same for Codex. The widget itself mirrors this: a provider that is not installed is hidden from the layout entirely rather than rendered with a placeholder. The companion preview pane lets you flip between Live, Both, Claude only, and Codex only so you can audit every state without changing your real install.

AI Usage is signed with a Developer ID Application certificate, hardened-runtime enabled, and notarized + stapled by Apple. The DMG opens cleanly on any Mac with no Gatekeeper warning. The whole repo is XcodeGen-driven, one project.yml describes the host app and widget extension targets, and a single release.sh produces a notarized DMG end to end.