OpenAI Codex pricing change detected: floor $0 → $8/mo

Detected automatically from the vendor pricing page. Individual plans include Free, Go ($8/month), Plus ($20/month), and Pro (starting at $100/month); Business plans are $25 per user per month when billed monthly, and Enterprise requires contacting sales; an API Key option is available for usage-based pricing. Pending human verification (needs_review).