Cloudflare Browser Run adds guardrails: whitelist hostnames for agent browser sessions
ritakozlov · x · 2026-09-16
Cloudflare's Browser Run, a hosted way to give agents a safe browser, now supports guardrails that restrict a session's HTTP/HTTPS requests to whitelisted hostnames.
- Use cases: confine a browser workflow to one site and its subdomains, load only known third-party APIs/scripts/fonts, or render HTML to screenshots/PDFs without external content.
- Usage: pass guardrails.allowedDomains (e.g. ["example.com", ".example.com"]) when launching Puppeteer/Playwright or via the REST API.
- Live View also gains a read-only mode: generate a { mode: "readonly" } link so viewers can watch a session without clicking, typing, navigating, or running JavaScript, without changing session hostname restrictions.
Rita Kozlov calls it the easiest way to give agents a (safe) browser you can actually trust.
More from coding & agent
- Clay built agents on Vercel AI SDK; LangSmith tracing took one line — LangChain · 2026-09-17
- Sentry founder questions the value of WebMCP, asks for a killer use case — zeeg · 2026-09-17
- Sentry CEO David Cramer doubts WebMCP's value, clashing with Wes Bos's hype — zeeg · 2026-09-17
- happyrobot podcast breaks down the FDE motion and why it breaks at 60 engineers — ivory_tang · 2026-09-17
- HashiCorp founder's "whiteboard defense": can you explain any AI-assisted system you shipped? — charles_irl · 2026-09-16
- Production team has editors narrate their cuts to train future AI editing agents — alexgoughcooper · 2026-09-16