Claude Code’s In-App Browser Lets Claude Test Live Sites

Anthropic put a tabbed in-app browser inside the Claude Code desktop app in the week of July 6, 2026. Claude can open docs, designs, and other sites, then read, click, and type the way it already tests a local dev server.

Fewer Chrome trips is the surface change. The agent can now see the live web, and Anthropic split that eye from your real logins on purpose.

Week 28 Opened the Preview Pane to the Whole Web

The Code tab already had a preview for a running app. Claude can start a dev server, open it in the Browser pane, take screenshots, inspect the DOM, click elements, fill forms, and fix what it finds. Static HTML, PDFs, images, and videos from the project open there too.

Week 28, shipping as Claude Code v2.1.202 to v2.1.206 from July 6 to 10, 2026, extended that pane to any site. On July 10, ClaudeDevs, Anthropic’s developer account on X, said Claude can “pull up docs, designs, or any other site” and “interact the same way it does with your local dev servers.”

Claude Code on desktop now has an in-app browser.

Claude can pull up docs, designs, or any other site. It can read, click through, and interact the same way it does with your local dev servers.

It's sandboxed and configurable: you choose whether sessions persist. pic.twitter.com/Jbc21OP0vJ

— ClaudeDevs (@ClaudeDevs) July 10, 2026

The Claude desktop app has three tabs, Chat, Cowork, and Code. This browser lives in Code. Open it with Cmd+Shift+B on macOS or Ctrl+Shift+B on Windows, or pick it from Views. It sits in the same drag layout as chat, diff, terminal, and the file editor.

HOW THE EYE SHOWED UP

1. March 30 to April 3, 2026: Computer use reaches the Claude Code CLI in research preview, so Claude can click through native apps from the terminal.
2. June 29 to July 3, 2026: Claude in Chrome is generally available on direct Anthropic plans, the week before the in-app pane.
3. July 6 to 10, 2026: Desktop Code gets the built-in browser for external sites, sandboxed, with a user choice on whether sessions persist.
4. July 20 to 24, 2026: Desktop opens an iOS Simulator pane so Claude can run and tap an iOS app without turning on computer use.
5. August 26, 2026: Cowork gets its own built-in browser in the same desktop app, 47 days after the Code announcement.

Anthropic’s April 14, 2026 desktop redesign had already added an expanded preview for HTML, PDFs, and local app servers. Week 28 is the step that lets the same pane leave localhost.

A Clean Profile Is the Point of the Split

The tabbed Browser pane in Claude Code uses a clean browser profile, separate from your personal browser, with none of your saved logins or history. You can still sign in from the pane, including popup flows such as Google OAuth. The missing piece is your existing identity, not the ability to log in.

When the job needs you, Anthropic points you at the Claude in Chrome extension, which shares Chrome’s login state. The in-app pane is for building, testing, and sites that do not need your accounts. That split is the product: the agent gets a browser without inheriting production cookies by default.

THREE WAYS CLAUDE REACHES A PAGE

Local preview can persist cookies and local storage across server restarts from the toolbar dropdown, so you are not logging into your own app on every boot. ClaudeDevs also said you choose whether browsing sessions persist. Saved data can be cleared, and the Browser can be turned off, in Settings under Claude Code.

What Claude Can Do on an External Site

Claude uses the same tools on an external page that it uses to check your app. It is not a read-only iframe you glance at while you type. The model can walk a flow, then keep editing code in the same session.

THE VERIFY LOOP INSIDE THE PANE

• Read the page: Claude opens docs, designs, issue trackers, or any other site next to the running app.
• Drive the UI: It clicks, types, and fills forms, including on the app it just served locally.
• Check its work: It takes screenshots and inspects the DOM, then patches issues it finds.
• Keep the session: You can persist cookies for local servers, and you can keep or reset browsing sessions.
• Stay in Code: Chat, diff, terminal, and the file editor stay in the same window while the pane runs.

People already use that loop on design work. Opening Claude Design in the desktop browser, then editing in chat and watching the artboard update, is a tighter path than bouncing from the CLI to a separate window. The same pattern applies to API docs and GitHub threads: the agent goes and looks, instead of waiting for a paste.

Classifiers Still Block Purchases and New Accounts

Write actions on external pages go through safety classifiers in every permission mode, the same checks auto mode uses on code. If a classifier flags an action, you get a prompt even in a loose mode. In modes other than Auto and Bypass permissions, a domain allowlist check also runs before Claude navigates to a new site.

The first time Claude acts on an external site, a permission card waits for Allow once, Always allow, or Deny. Always allow is saved on that device and can be revoked in Settings. Each site needs its own approval, including subdomains. Local dev servers and project files skip that card, so auto-verify on your own app does not stall.

Even on an approved site, Claude will not purchase items, create accounts, or bypass CAPTCHAs without you. The pane follows the same safety model as Claude in Chrome. Anthropic’s write-up of prompt injection defenses for browser use is the matching research track: hidden instructions in a page can still try to redirect an agent that can click.

Admins inherit the site allowlist and blocklist already set for Claude in Chrome. They can also disable Claude’s tools on external pages while leaving human browsing on, or block external navigation entirely. Localhost and file previews keep working in that last case.

The Pane Stops Drawing When You Look Away

The common complaint, that the pane cannot log in, is wrong. Pasquale Pillitteri, a software engineer who unpacked the macOS app bundle after the July 10 launch, found a different limit. Screenshots of the pane hang when the view is not visible, because the capture is a Chromium Page.captureScreenshot call that needs a fresh frame.

On the install he studied, the pane ran on Electron 42.5.1 with Chromium 148.0.7778.271. Electron’s default is to apply Electron background throttling on hidden views, which slows timers and can stop frames when a page is treated as hidden. Pillitteri wrote that Anthropic turns throttling off for detached windows and toggles it on the main view, but the browser view is created without that opt-out, so it keeps the default.

He also noted a quirk in Electron: if any view in a window has throttling off, the whole window keeps drawing. A detached window, or an active computer-use lock, can keep the pane awake by accident. Hide the app, and the compositor can stall. Playwright avoids this by launching Chromium with background timer throttling, occluded-window drawing, and renderer backgrounding turned off. Claude Code is an all-day desktop app, so a pane that never sleeps would burn CPU. The cautious default breaks unattended screenshot loops.

His capture settings on that build were a 1280×720 viewport, JPEG at quality 75, and a downscale to 800 pixels wide when the page is wider. That is one engineer’s reading of one bundle, not an Anthropic spec sheet, and it is the part of the “eye” that still blinks.

WHEN TO USE WHICH BROWSER

• Code pane: Frontend work with the pane visible, docs beside the diff, and sites that are safer on a clean profile.
• Claude in Chrome: Tasks that must run as you, inside sessions that already exist in your personal browser.
• Playwright or a headed test runner: CI, scheduled jobs, and any screenshot you need while the window is covered.
• Skip the pane: Unattended capture behind other apps, where Chromium will stop painting.

If the pane is not on screen, do not build a process that depends on it taking a picture.

Daily Use Still Hits Missing DevTools

Two months on, the pane still behaves like a preview that learned to leave localhost, not like a full browser that replaced Chrome. Developers who live in the desktop app all day still cannot open it before a chat starts, and they cannot open DevTools inside it. Cursor and Codex expose a fuller in-app browser, including a path that starts from a local URL and a screenshot, which makes a tiny UI fix feel smaller than waking a whole agent session.

Some Windows installs have crashed when the in-app browser is in use. Replies under the July 10 post also pushed Anthropic to keep spending on the desktop shell, because the terminal workflow still feels like a fallback rather than a home. The Code tab is the product those users want funded.

The pane is also the wrong tool when you need your real cookies on the first try. Sign-in works, and OAuth popups work, but a clean profile means you repeat that work unless you persist the session. For CRM, mail, and corp SSO, Claude in Chrome remains the path that already has your tabs.

Cowork Got Its Own Browser on August 26

Code and Cowork share a desktop window and not a browser. On August 26, 2026, Anthropic shipped a built-in browser in Claude Cowork for Pro, Max, and Team plans, with Enterprise admins able to turn it on the same day. It opens in a side panel when a task needs a site. Claude reads pages, clicks, and types, with no extension and nothing taken from your browser unless you choose to import logins site by site.

Anthropic’s line on that product is blunt: “It’s Claude’s browser, not yours.” Banking, email, and single sign-on stay out of an import unless you include them. If Claude in Chrome is already set up, it stays the default for Cowork web tasks; otherwise the built-in pane is used. You can switch under Settings, Cowork, Preferred browser.

The Cowork pane carries the same prompt-injection risk as any agent that acts on the public web. Anthropic says the safeguards reduce that risk and do not remove it, and it tells people to start on sites they trust. From the web or a phone, Claude can still drive the desktop browser while that app is open and online. Without the desktop app, Claude in Chrome is still the way to give Cowork a browser.

For Code users, the August sibling is confirmation, not a replacement. The company is putting a browser next to every long-running agent surface in the desktop app. The Code pane remains the one that shares a layout with diffs, the terminal, and a running dev server, and it remains the one that goes quiet when you look away.

Frequently Asked Questions

How Do I Open the Claude Code In-App Browser?

Besides the shortcut, you can open it from the Views menu. When you click an external link in chat, a chooser offers Open in app for the pane or Default browser for your own; Cmd-click on macOS or Ctrl-click on Windows sends the link to the system browser immediately.

Does the In-App Browser Use My Chrome Logins?

No. It starts with a clean profile and none of your history. You can sign into a site from the pane, including Google OAuth popups, and you can persist local-server cookies from the toolbar so a dev login survives a restart. Clear that saved data, or turn the Browser off, in Settings under Claude Code.

Is the In-App Browser in the Claude Code CLI?

No. The Browser pane is a Desktop Code-tab feature. The CLI got computer use in research preview in the week of March 30, 2026, which is screen control for native apps, not this tabbed pane. Cloud sessions also do not get a popped-out terminal pane to move around.

Can Admins Block Claude From Browsing External Sites?

Yes. The pane respects the same site allowlist and blocklist as Claude in Chrome, so those lists apply without a second setup. The browserExternalPageTools managed setting strips Claude’s tools on external pages while people can still browse them, and disableBrowserExternalNavigation blocks external sites for both users and Claude while localhost and file previews keep working.

Enterprise admins who want a hard off switch already have it. Localhost preview survives that switch. The live web does not.