Cloudflare agents can preview private dev servers without public URLs
Cloudflare added internal hostnames to Browser Run and Agents SDK 0.31.0, allowing a persistent agent browser to reach sandbox ports, workspace folders or service-bound Workers through schema-validated private hosts without publishing the target to the Internet.
Why it matters: Coding agents can perform browser QA against ephemeral private builds while reducing accidental exposure, but the internal-host callback becomes a privileged routing boundary.