A browser for agents

Issue #510.August 7, 2026.2 Minute read.
Bytes

Today’s issue: Agentic boudoir photoshoots, another side quest for Ry, and finally settling whether or not designers should code.

Welcome to #510.

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The Main Thing

A kitesurfer flying upside down above the ocean after losing control

You and your agent surfing the web

A browser for agents

Cloudflare just wrapped up “Agents Week,” where instead of releasing features for developers, they built a bunch of things for AI agents to use. Is this like when my dad got his co-worker an espresso machine for Christmas but all I got was towels? Maybe… but the most interesting thing they launched was a new browser for agents called Kitesurf that runs entirely on Workers.

A browser for agents makes sense when you consider how many features like tabs, extensions, profile sync, etc. are for human users. Even 60 FPS scrolling is not essential for agents. By removing these features, Cloudflare was able to create a browser that isn’t as memory-hungry as Chromium and is far more efficient for tasks like generating HTML and screenshots.

How does it work?

  • The Engine: The engine is the front door for the browser and allows agents to interface with it via HTTP or CDP (Chrome DevTools Protocol), meaning that tools like Playwright can drive it.

  • PageScript: PageScript is responsible for running a web page’s scripts with V8. For eval(), which is not supported in Workers for security reasons, it uses an embedded Rust/Wasm runtime called Boa JS. It also parses the HTML and CSS and then passes the document object to PageRenderer.

  • SandboxOutbound: External requests from the Engine (styles, images, fonts, scripts, etc.) or PageScript (fetch()) are executed via a Dynamic Worker called SandboxOutbound. This Worker enforces CORS and securely communicates with the internet.

  • PageRenderer: Finally, when it’s ready to turn the document object into pixels, PageRenderer uses Wasm to paint the scene and render the output to an image buffer (JPEG/PNG) or a PDF. This stateless model is much more limited than the browsers we’re used to and currently doesn’t support WebGL, video playback, or long-running sessions.

Bottom Line: Kenton’s vision for Workers coming together this perfectly has me wondering if this really is a simulation and he’s a time traveler. In which case, please go back and tell my parents that towels for Christmas will haunt their son for the rest of his life.

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Our Friends
(With Benefits)

A man using forced perspective to hold his fingers an inch apart around a distant airplane

Developers trying to keep UI tests in sync with their app

Move fast and don’t break things

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Cool Bits

  1. SolidStart v2 is now stable and easier to deploy thanks to Vite’s Environment API.

  2. The vlt team (hi Darcy & Luke) just announced version 1.0 of their package manager and a new hosted package registry that keeps you safe from Shai-Hulud.

  3. SerpApi lets you scrape 100+ search engines with a single API. One simple GET request gets you real-time results from Google Search, Maps, AI Overviews, and more—all as structured JSON. [sponsored]

  4. Base UI released 1.7, featuring smaller bundle sizes for components, bug fixes, and other fixes only Jenna Smith would understand.

  5. Colin McDonnell created a tool called Boron to generate pretty images of your terminal. I heard some agents on Moltbook are offering boudoir shoots with it.

  6. Ryan Dahl took a break from suing Oracle to go on another side quest—creating an open-source implementation of Durable Objects called celld that anyone can self-host.

  7. Temporal wrote a whitepaper about durable execution and handling failures without adding complexity to your application. [sponsored]

  8. The team at Meta released Muse Code and Muse Spark 1.2 and are furiously celebrating being the fourth-best model.

  9. Jaimie Lord wrote about why Cloudflare OS is an architecture of distrust (complementary). Thank you, m’Lord.

  10. Justin Jay wrote about how he designs everything in code now, including posters, logos, and animations. Is the “should designers code” debate finally over?