First the page gave me an error message. I refreshed and then it said my browser was "out of date" (read: fingerprint resistance is turned on). Turned that off and now I just get an endless captcha loop.
tl;dr OpenAI provided, a default-disabled, beta MCP interface. It will allow a person to view and enable various MCP tools. It requires human approval of the tool responses, shown as raw json. This won't protect against misuse, so they warn the reader to check the json against unintended prompts / consequences / etc.
I give up.