Agentic WeeklyGet the weekly

Cloudflare Agents SDK 0.31.0 adds internal hostnames to the browser and makes MCP packages optional

Release Ruler for this brief: marked at its publication date, Oct 27, 2026, among the AI models we track.

Cloudflare Agents SDK agents@0.31.0 (October 27, 2026) lets a Browser Run browser send requests for up to 8 internal hostnames to your agent instead of the internet, makes @modelcontextprotocol/sdk and @modelcontextprotocol/server optional peer dependencies that MCP users must now add themselves, and runs browserTool's model code in its own Dynamic Worker.

By Agentic Weekly · Evidence: Reported · How we work

First seen
(via GitHub releases: cloudflare/agents)
Source published
(we saw it 40 minutes later)
Brief published

What changed

  • Internal hostnames: browserRun() accepts up to 8 hostnames as internalHosts, and requests to them are served by a fetch function on your agent or by another Worker, so the model can open a dev server or workspace folder in the same browser it uses for the web.
  • With a target schema on a host, the model itself picks what the host serves through browser.assignHost(), such as a container port or a workspace folder.
  • Breaking for MCP users: @modelcontextprotocol/sdk and @modelcontextprotocol/server are now optional peer dependencies; anyone using agents/mcp, agents/mcp/server, agents/x402 or agents/experimental/webmcp must add them (sdk 1.32.1, server 2.3.1) or builds fail.
  • browserTool now runs the model's code in its own Dynamic Worker instead of on codemode, the model calls browser.cdp() instead of cdp.send(), and results carry a notice field in place of restarted, newTabs and calls.
  • createBrowserTools, createBrowserRuntime, BrowserConnector and the Quick Action helpers are deprecated in favour of browserTool, while agents/models/ai-sdk and agents/models/pi-ai are no longer experimental.
  • The companion @cloudflare/think 0.22.0 removes lazyWorkspace, exported by mistake in 0.21.0, and now needs @cloudflare/computer 0.8 as its peer.

In the source’s words

“Until you do, builds fail with an unresolved import.”

Early verdict

If you serve MCP from Cloudflare Agents, add the two MCP packages to package.json before upgrading; if you use browserTool, follow the three upgrade steps in the notes.

Basis: Based only on the agents@0.31.0 release notes; we have not run this version.

What we have not verified

  • We did not run this release ourselves or test internal hostnames.
  • The release notes do not say whether Browser Run pricing or limits change with internal hostnames.
  • We did not check when the deprecated browser helpers will be removed; the notes give no date.

This brief is Reported: written from the sources below, not from running the release ourselves.

Sources

Spotted an error? See our corrections policy or email the address on the contact page. Markdown version for agents: /news/cloudflare-agents-0-31-0.md

Want these briefs in your Google Top Stories? Add Agentic Weekly as a preferred source on Google.