[BUG] Cowork fails on macOS - checks for bubblewrap (Linux-only) instead of using Seatbelt

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?

Cowork fails to start on macOS with error: "Sandbox dependencies are not available on this system. Required: ripgrep (rg), bubblewrap (bwrap), and socat."

This is incorrect - bubblewrap is a Linux-only containerization tool. macOS should use Seatbelt for sandboxing, as documented in Claude Code's own docs: https://code.claude.com/docs/en/sandboxing

"macOS: Uses Seatbelt for sandbox enforcement"

What Should Happen?

Cowork should use Seatbelt on macOS, not check for Linux-specific dependencies.

Error Messages/Logs

CLI output was not valid JSON. This may indicate an error during startup.
Output: Error: Sandbox dependencies are not available on this system.
Required: ripgrep (rg), bubblewrap (bwrap), and socat.

Steps to Reproduce

1. Open Claude desktop app on macOS
2. Go to Cowork tab
3. Send any message

Claude Model

Not sure / Multiple models

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.1.15

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

• ripgrep exists and works fine (bundled with claude-code)
• bubblewrap does not exist for macOS - it's Linux-only
• socat can be installed but doesn't help since bwrap check fails
• The check appears to happen before any config files are read, so sandbox.enabled: false has no effect