[BUG] bash_tool runs in Anthropic Linux sandbox instead of local macOS environment

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?

When using Claude Code on macOS, bash_tool executes inside Anthropic's cloud Linux sandbox (Linux runsc, x86_64) instead of the local macOS filesystem.

The system prompt declares "macOS Claude Code environment" but bash_tool actually runs on Linux. This means ~/.claude/ is completely inaccessible, local project files cannot be read or written, and Claude cannot access its own configuration.

Additionally, the bug is self-concealing: Claude cannot report this issue through its own tools because bash_tool cannot reach the macOS app layer, no Report Issue UI exists in the app, and files saved by bash_tool (/home/claude/) are lost when the session ends.

What Should Happen?

Option A (preferred): bash_tool should execute on local macOS when running in Claude Code desktop app, giving genuine access to ~/.claude/, local projects, and native tools.

Option B (acceptable): If cloud-only execution is by design, all system prompts and documentation must clearly state this so users are not misled.

Error Messages/Logs

1. Launch Claude Code on macOS
2. Ask Claude to run: uname -a
3. Observe result is "Linux runsc" not "Darwin"
4. Ask Claude to read ~/.claude/CLAUDE.md
5. Observe: file not found (Linux sandbox cannot access macOS filesystem)

Steps to Reproduce

1. Launch Claude Code on macOS
2. Ask Claude to run: uname -a
3. Observe result is "Linux runsc" not "Darwin"
4. Ask Claude to read ~/.claude/CLAUDE.md
5. Observe: file not found (Linux sandbox cannot access macOS filesystem)

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude 1.1.7714

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

During this session, Claude attempted to self-report this bug but failed at every step:

• Saved report to /home/claude/ (Linux sandbox, lost on session end)
• No Report Issue UI exists in the app
• /bug slash command requires CLI which was removed
• Cannot send feedback programmatically from Linux sandbox

The system cannot report its own bug through its own tools. This is a compounding failure.

Workaround: Users must install Desktop Commander MCP server to access local macOS filesystem. This should not be required for basic local development functionality.