[ben-reitz]

Summary

browserTool runs the model's code in its own Dynamic Worker on a new BrowserSession, instead of on @cloudflare/codemode.

 browserTool(code)
-  codemode executor
-    BrowserSessionConnector (cdp.*)
+  runBrowserCode            # sandbox.ts: Dynamic Worker, globalOutbound: null, host-side deadline
+    cdp.* → BrowserSession  # session.ts: one run's connection to the browser
+  session.close() → report  # restarted, newTabs, tabClosed, tabShared

• browser.session({ scope }) is public, so your own code gets the same sessionId: "active" handling, validation and error hints.
• browserTool no longer needs ctx or a CodemodeRuntime export, and its output drops the calls log. @cloudflare/codemode must stay installed while agents/browser still exports the deprecated codemode APIs.
• Model code can't close or crash the browser, mint a Live View link (Cloudflare.getLiveView, Cloudflare.handoff), or tunnel commands past that check (Target.sendMessageToTarget, Target.exposeDevToolsProtocol).
• The host enforces the run timeout too, so code that cancels the sandbox's timer can't hold the scope's queue.
• A returned browser_screenshot is kept whole only if it's a png, jpeg or webp of base64 data under 1 MB; anything else is cut down like any result. Console logs are capped at 100 lines.
• session-connector.ts is gone; truncate.ts keeps results under the token budget.

Ported from #2612 by @mattzcarey (co-authored). Computer ws:browser mentions are removed here; that comes later in its own PR. This stack supersedes #2612.

[changeset-bot]

🦋 Changeset detected

Latest commit: cf57109

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
agents	Minor
@cloudflare/agent-think	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[agent-think]

🔴 agents import sizes: 1 entry point over threshold

	Entry point	Exports	Largest gzip change	Size now
🔴	agents/browser	1 resized, 2 new	+6.4 KiB (+15.53%)	47.8 KiB
🟡	agents/browser/ai	2 resized	up to +1.2 KiB (+0.79%)	149 KiB
🟢	agents/browser/pi	1 resized	-43 KiB (-55.53%)	34.4 KiB
🟢	agents/browser/ai-sdk	1 resized	-8.7 KiB (-6.13%)	133.9 KiB
🟢	agents/browser/tanstack-ai	1 resized	-8.7 KiB (-5.52%)	149.5 KiB

Changed exports (8)

	Import	Gzip change	Size now
🔴	agents/browser#Browser	+6.4 KiB (+15.53%)	47.8 KiB
🟡	agents/browser/ai#createBrowserTools	+1.2 KiB (+0.79%)	149 KiB
🟡	agents/browser/ai#createBrowserRuntime	+1.2 KiB (+0.79%)	149 KiB
🆕	agents/browser#BrowserSession	—	42.8 KiB
🆕	agents/browser#ACTIVE_PAGE_SESSION	—	35.9 KiB
🟢	agents/browser/pi#browserTool	-43 KiB (-55.53%)	34.4 KiB
🟢	agents/browser/ai-sdk#browserTool	-8.7 KiB (-6.13%)	133.9 KiB
🟢	agents/browser/tanstack-ai#browserTool	-8.7 KiB (-5.52%)	149.5 KiB

How this works

Each runtime export is bundled on its own, minified, and gzipped. Changes smaller than 100 B, or smaller than 1% and 1 KiB, are ignored. Growth over 10% or 5 KiB is marked 🔴. This report is informational and does not fail CI. The workflow artifact contains every measurement.

_{Compared 5e7f5515 → cf57109f · workflow run · reported by agent-think[bot]}

[pkg-pr-new]

Open in StackBlitz

agents

npm i https://pkg.pr.new/agents@2667

@cloudflare/ai-chat

npm i https://pkg.pr.new/@cloudflare/ai-chat@2667

@cloudflare/codemode

npm i https://pkg.pr.new/@cloudflare/codemode@2667

hono-agents

npm i https://pkg.pr.new/hono-agents@2667

@cloudflare/shell

npm i https://pkg.pr.new/@cloudflare/shell@2667

@cloudflare/think

npm i https://pkg.pr.new/@cloudflare/think@2667

@cloudflare/voice

npm i https://pkg.pr.new/@cloudflare/voice@2667

@cloudflare/worker-bundler

npm i https://pkg.pr.new/@cloudflare/worker-bundler@2667

commit: cf57109