[BUG] owork Domain allowlist UI not honored by sandbox proxy

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?

[BUG] Cowork Domain allowlist UI not honored by sandbox proxy — api.chartmetric.com blocked despite being saved in allowlist
Use the bug report text I drafted earlier as the body. Add the literal proxy response we captured (X-Proxy-Error: blocked-by-allowlist) — that header makes it a tight reproducible bug, not a vague "doesn't work" complaint.
OS version (Windows 11 build number)
The curl -v output from my earlier test showing the 403 with that header

<img width="1800" height="847" alt="Image" src="https://github.com/user-attachments/assets/4593f65e-0530-45db-a4a2-c5555350230b" />

What Should Happen?

cowork should be able to access this api url to write a python script

Error Messages/Logs

Steps to Reproduce

Title: [BUG] Cowork Domain allowlist UI not honored by sandbox proxy — api.chartmetric.com blocked despite being saved in allowlist
Use the bug report text I drafted earlier as the body. Add the literal proxy response we captured (X-Proxy-Error: blocked-by-allowlist) — that header makes it a tight reproducible bug, not a vague "doesn't work" complaint.

Claude Model

Opus

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.1.114 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_