Sandbox: zsh writes to /tmp/claude-501/cwd-* causing 'operation not permitted' errors

Description

Every Bash tool invocation produces a noisy zsh:1: operation not permitted: /tmp/claude-501/cwd-XXXX error, even though the actual command succeeds. This pollutes tool output and causes misleading non-zero exit codes.

Steps to Reproduce

1. Run any Bash command via Claude Code (e.g., git status)
2. Observe the error in output:

``
zsh:1: operation not permitted: /tmp/claude-501/cwd-6648
``

Expected Behavior

No sandbox permission errors from shell internals.

Actual Behavior

Every command produces zsh:1: operation not permitted: /tmp/claude-501/cwd-XXXX. The path changes each invocation (random suffix). The actual command executes successfully, but exit code may be affected.

Analysis

• The sandbox write allowlist includes /tmp/claude and /private/tmp/claude, but not /tmp/claude-501/.
• Something in the shell initialization (zsh hook or prompt function) attempts to write the current working directory to /tmp/claude-501/cwd-XXXX.
• This is not caused by user zsh configuration (~/.zshrc, ~/.zprofile — confirmed clean).
• The 501 in the path likely corresponds to the macOS user UID.

Environment

• OS: macOS (Darwin 24.6.0)
• Shell: zsh
• Claude Code model: claude-opus-4-5-20251101

Workaround

None needed functionally — commands execute correctly. The error is cosmetic but causes confusing exit codes and noisy output.