Monitor Your AI Coding Assistant Usage Limits on macOS with CodexBar

Overview

If you use AI coding assistants like Claude Code, GitHub Copilot, Cursor, OpenAI Codex, or Gemini CLI, you've probably hit a usage limit mid-task and had to guess when it would reset. CodexBar is a free, open-source macOS menu bar app that keeps your session limits, weekly quotas, credits, and reset countdowns visible at a glance — no logging into dashboards, no guessing.

This article covers how to install CodexBar, configure it for the AI tools you actually use, and what permissions to expect.

Who this is for

Mac users on the Clark School who:

• Use one or more AI coding assistants regularly (Claude Code, Copilot, Cursor, Codex, Gemini, etc.)
• Want to avoid getting locked out of an AI tool in the middle of a working session
• Prefer a lightweight native menu bar tool over checking provider dashboards in a browser

Requirements

• macOS 14 (Sonoma) or later — Apple Silicon or Intel
• The CLI, browser session, or API credential for whichever AI provider(s) you want to monitor (CodexBar reads from these — it does not log in for you)

Supported providers

CodexBar tracks usage for ~29 providers, including: Claude (Code), OpenAI Codex, Cursor, GitHub Copilot, Gemini, Antigravity, Droid (Factory), z.ai, Kimi / Kimi K2, Kiro, Vertex AI, Augment, Amp, JetBrains AI, and OpenRouter.

You only need to enable the providers you actually use — don't enable everything.

Installation

You can install CodexBar one of two ways. Pick whichever fits your workflow.

Option 1: Homebrew (recommended)

If you have Homebrew installed, run:

brew install --cask steipete/tap/codexbar

This is the easiest path and gives you automatic updates via Sparkle.

Option 2: Direct download

1. Go to the CodexBar GitHub Releases page.
2. Download the latest .dmg file.
3. Open the .dmg and drag CodexBar.app into your /Applications folder.
4. Launch CodexBar from Applications. You may need to right-click → Open the first time to bypass Gatekeeper.

First-run setup

1. Launch CodexBar. A small two-bar meter icon will appear in your menu bar — there is no Dock icon by design.
2. Click the menu bar icon and choose Settings → Providers.
3. Toggle on only the providers you use (e.g., Claude, Copilot, Cursor).
4. For each enabled provider, make sure you're already signed in to its source. Depending on the provider, that means one of:
   • The provider's CLI is installed and authenticated (e.g., claude, codex, gemini)
   • You're signed in to the provider in your browser (Safari/Chrome/Firefox/Edge), so CodexBar can read the session cookie
   • You've completed an OAuth or device flow inside CodexBar's settings
   • You've pasted an API token into CodexBar's settings (stored in macOS Keychain)
5. Optional: under Settings → Providers → Codex → OpenAI cookies, enable cookie reading to get extra dashboard info like code review remaining and usage breakdown.

How to read the menu bar icon

The icon is a tiny two-bar meter:

• Top bar: your 5-hour / session window. If your weekly limit is exhausted but you have credits, this becomes a thicker credits bar.
• Bottom bar (hairline): your weekly window.
• Dimmed icon: stale data or an error reading from the provider.
• Status overlay: indicates a provider-side incident (e.g., Anthropic or OpenAI is having an outage).

Click the icon any time to see the full breakdown, including precise reset countdowns.

macOS permission prompts (what to expect)

CodexBar is designed to be privacy-respecting — it does not crawl your filesystem and does not request Screen Recording, Accessibility, or Automation permissions. However, depending on which providers you enable, macOS may prompt you for the following:

• Full Disk Access (only if using Safari cookies for web-based providers) — System Settings → Privacy & Security → Full Disk Access. If you don't want to grant this, use Chrome/Firefox cookies or CLI-only sources instead.
• Keychain access prompts — Required so CodexBar can read your Claude OAuth credentials, Chrome's Safe Storage key (to decrypt browser cookies), or stored API tokens for providers like z.ai and Copilot.
• Files & Folders prompts — If CodexBar invokes a provider CLI (e.g., claude, codex) and that CLI reads from a project directory or external drive, macOS may prompt CodexBar for access to that folder.

Stop the repeating Keychain prompts

If macOS keeps prompting you to allow Keychain access every time CodexBar refreshes:

1. Open Keychain Access.app.
2. Select the login keychain and search for the relevant item (e.g., Claude Code-credentials for Claude, or Chrome Safe Storage for Chrome cookies).
3. Double-click the item and go to the Access Control tab.
4. Click + and add CodexBar.app under "Always allow access by these applications."
5. Save and relaunch CodexBar.

Add CodexBar specifically rather than choosing "Allow all applications" so you keep the rest of your Keychain locked down.

Privacy and security notes

• CodexBar is open source under the MIT license. Source code: github.com/steipete/CodexBar
• Parsing happens on-device by default. Browser cookie usage is opt-in per provider.
• No passwords are stored. CodexBar reuses existing browser cookies or OAuth tokens you've already authorized.
• It reads from a small set of known locations (provider config files, browser cookie databases, local JSONL logs) — it does not scan your disk.

Use the bundled CLI (optional)

CodexBar ships with a codexbar command-line tool that's useful for scripting, CI checks, or quick terminal lookups. For example, to see your local Codex and Claude cost usage for the last 30 days:

codexbar cost --provider codex
codexbar cost --provider claude

The CLI is also available as a standalone install on Linux via Homebrew if you want usage info on a non-Mac dev box.

Troubleshooting

Support

• CodexBar issues / bugs: Report directly to the upstream project at github.com/steipete/CodexBar/issues. CodexBar is a third-party open-source tool and is not supported by Engineering IT.
• Engineering IT support: If you need help with installation on a managed Clark School Mac or have questions about appropriate use of AI coding assistants, contact Engineering IT through the standard support channel.

Related resources

• CodexBar website: https://codexbar.app/
• CodexBar source code and docs: https://github.com/steipete/CodexBar