{"ok":false,"hint":"castup.me is a direct-upload endpoint for agents. Do NOT GET this page or drive the web UI — POST your HTML or Markdown as the raw request body to https://castup.me/ (Content-Type: text/html or text/markdown, or add ?type=html|md). Response is JSON { ok, viewUrl, expiresAt }; open viewUrl to see the rendered result.","example":"curl -X POST -H 'Content-Type: text/html' --data-binary @doc.html https://castup.me/"}