[BUG] I can't update my Vercel alias in Claude Code (cloud - web or app)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

I have to run my branches at preview.<mydomain>.com for my auth to work - I'm using vercel for my deployments. I created a /preview claude code command so when I'm working in claude code in the app or on the web I can have claude take the branch it made and set the vercel preview. domain to point at the branch claude created. But all of my commands fail. Claude says it's because api.vercel.com isn't allowed egress access from the claude code web/app sandbox environment. Help!

What Should Happen?

Claude should allow this access.

Error Messages/Logs

Steps to Reproduce

From Claude Code web/app, try to update a Vercel domain alias to point at a Claude code branch. It fails.

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

4.5

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_