C5h

Schedule and run AI provider CLIs in planned and background windows.

C5h is a native macOS app that tracks your Claude and Codex 5-hour usage windows in one place. See which windows are active on a day calendar, schedule prompts to run inside planned or background windows, and watch your usage trends over time, so you always know where you stand against your limits before you hit them.

Features

• Track 5-hour windows: Claude and Codex usage windows, side by side.
• Day calendar: see active and upcoming windows laid out on a timeline.
• Connect your CLIs: point C5h at your installed claude and codex CLIs.
• Usage trends: area and sparkline charts of usage over time.
• Scheduled & background runs: queue prompts to run automatically inside a window, even when you're away.

Requirements

• macOS Tahoe (macOS 26) or later.

• The claude and codex CLIs installed and authenticated:

  claude --version
  codex --version

Install

Homebrew (recommended):

brew install --cask zaai-com/tap/c5h

Direct download: download the latest C5h-<version>.dmg from GitHub Releases, open it, and drag C5h.app to your Applications folder. The app is signed and notarized.

First run

1. Launch C5h. A short onboarding walks you through what the app tracks.
2. Open the Providers tab and use Detect CLI to find your claude and codex binaries. If a CLI lives outside the standard lookup paths, use CLI path… to point at it directly.
3. Your windows and usage start populating as the CLIs report activity.

Where C5h stores data

The app keeps its database and logs under:

~/Library/Application Support/C5h

Removing that folder resets the app to a clean state.

Build from source

C5h is a Swift / SwiftUI Xcode app. With the latest Xcode installed:

xcodebuild -workspace C5h.xcworkspace -scheme C5h \
  -configuration Debug -destination 'platform=macOS' build

For the full development runbook (architecture, packages, the background helper, and scheduled-run testing) see .claude/CLAUDE.md.

License

C5h is released under the MIT License.