Browser pane tool fails on all read/screenshot calls with "Policy check temporarily unavailable"

### Preflight Checklist

- [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) 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?

The in-app "side browser" pane (Claude Browser tool) opens and connects fine — tab-context checks succeed — but every call that reads or views page content (screenshot, get_page_text, read_page, find) fails immediately with:

"Policy check temporarily unavailable; retry."

This has persisted for ~24 hours across multiple sessions. A full restart of the Claude Code desktop app did not resolve it (the app restart did clear a separate symptom where the pane was stuck showing a stale page, but the underlying read/screenshot error remains identical after restart).

Platform: Windows 11 Pro
Claude Code: desktop app

### What Should Happen?

The browser tool should be able to take a screenshot or read the page content instead of failing immediately.

### Error Messages/Logs

```shell
Policy check temporarily unavailable; retry.
```

### Steps to Reproduce

1. Open the Claude Browser pane / navigate to any page
2. Call any read/view action (screenshot, get_page_text, read_page, find)
3. Error returned immediately every time

### Claude Model

Sonnet (default)

### Is this a regression?

I don't know

### Last Working Version

_No response_

### Claude Code Version

1.46388.3.0

### Platform

Anthropic API

### Operating System

Windows

### Terminal/Shell

Windows Terminal

### Additional Information

_No response_

Start by reproducing on Windows 11 with Claude Code desktop app 1.46388.3.0, using the browser pane actions named in the issue: screenshot, get_page_text, read_page, and find. Then trace where the message "Policy check temporarily unavailable; retry." is returned for browser read/view calls. Done means those actions can read or view page content instead of failing immediately, or the failure is narrowed to the external policy check.

Written by the indexing model from the issue text.