OpenAI's Codex can now access the Chrome DevTools Protocol (CDP) inside its Browser Use feature, giving the agent direct visibility into console logs, runtime errors, local storage, applied styling, network traffic, and performance profiles during live web sessions.
The demo shows Codex diagnosing a slow chat application by running performance profiles and inspecting network requests, then patching the bottlenecks and backing every fix with measured before-and-after data. That workflow, profiling first and fixing second with hard numbers attached, is the part worth watching in full.
To activate it, turn on Developer Mode in Codex app browser settings and approve CDP access when prompted. The capability is live now, documented at developers.openai.com/codex/app/browser.
[WATCH ON YOUTUBE →]