AI Limits

A VS Code extension that shows your Claude and Codex (ChatGPT) usage budgets directly in the status bar — no separate configuration required.

Features

• Claude budget – powered by the Claude Code extension login
• Codex budget – powered by the ChatGPT extension login
• Quick jump to account settings – click either status bar meter to open that service's settings page
• Displays last 5 hours and last 7 days cost in the status bar
• Tooltip shows detailed breakdown including limit (if one is configured)
• Auto-refreshes every 5 minutes and whenever authentication sessions change

Requirements

Install at least one of the companion extensions and sign in:

AI Limits will only show a status bar item for extensions that are both installed and authenticated. If neither is present, the extension activates silently with no UI impact.

Status Bar Format

$(pulse) Claude 5h:$0.12 7d:$1.45   $(pulse) Codex 5h:$0.05 7d:$3.20

Hover over an item for a detailed tooltip with exact figures and any configured spending limits.

How It Works

1. On startup the extension checks whether anthropic.claude-code and/or openai.chatgpt are installed.
2. For each installed extension it reads credentials from the same on-disk / keychain location that extension uses (no separate login is ever required):
   • Claude Code: reads the macOS Keychain entry for service "Claude Code-credentials" (account = $USER). Falls back to ~/.claude/.credentials.json on non-macOS systems or if the keychain is unavailable.
   • OpenAI / Codex: reads ~/.codex/auth.json (or $CODEX_HOME/auth.json), which the local Codex agent daemon maintains.
3. The extension resolves usage data from the most reliable source available:
   • Anthropic: GET https://api.anthropic.com/v1/usage with start_time / end_time query parameters
   • OpenAI API key auth: GET https://api.openai.com/v1/usage?date=YYYY-MM-DD plus GET /v1/dashboard/billing/subscription
   • Codex ChatGPT OAuth auth: reads the latest local Codex session rollout (~/.codex/sessions/**/rollout-*.jsonl) and uses the embedded rate_limits snapshot (300 min and 10080 min windows)
4. Costs are displayed in USD. Where the API does not return cost directly, costs are estimated from token counts using current list pricing.

Known Limitations

Anthropic Usage API Scope

The OAuth token stored by Claude Code has the user:inference scope (for making model calls). Anthropic's usage/billing API may require a different scope or an admin API key. If the status bar shows $(warning) Claude: error and the tooltip says HTTP 403, the token does not have access to the usage endpoint. There is currently no workaround for consumer claude.ai accounts; the error state is shown rather than hiding the item entirely.

5-hour window (OpenAI API key mode)

OpenAI's usage endpoint returns data aggregated by UTC calendar day. The 5-hour figure is pro-rated from today's usage based on the elapsed fraction of the day, so it is an approximation.

Codex ChatGPT OAuth mode

When authenticated via ChatGPT OAuth (no OPENAI_API_KEY), the extension shows rate-limit utilization percentages for the 5-hour and 7-day windows from Codex's local session snapshot, instead of USD spend.

Cost estimation

When the API response does not include a pre-computed cost field, costs are estimated using hardcoded list pricing:

Actual costs may differ if you use other models or have negotiated pricing.

Development

# Install dependencies
npm install

# Compile TypeScript
npm run compile

# Run tests (requires VS Code to be installed)
npm test

# Watch mode
npm run watch

Project Structure

src/
  extension.ts          Entry point; wires providers, status bar, and refresh timer
  types.ts              Shared TypeScript interfaces
  statusBarManager.ts   Creates and updates the two status bar items
  providers/
    claudeProvider.ts   Fetches usage from the Anthropic API
    openaiProvider.ts   Fetches usage from the OpenAI API
test/
  runTests.ts           Launches the VS Code Extension Development Host test runner
  suite/
    index.ts            Mocha suite loader
    claudeProvider.test.ts
    openaiProvider.test.ts
    statusBarManager.test.ts

License

MIT