Claude Code fails to start when additionalDirectories contains a non-existent path

Summary

Claude Code becomes completely non-functional (offline/fails to start) when additionalDirectories in settings.local.json contains a path that no longer exists on disk.

Steps to reproduce

1. Add a non-existent directory to additionalDirectories in ~/.claude/settings.local.json:

``json
{
"permissions": {
"additionalDirectories": ["/some/path/that/does/not/exist"]
}
}
``

1. Restart Claude Code.

Expected behaviour

Claude Code starts normally and logs a warning such as:

"Directory /some/path/that/does/not/exist in additionalDirectories not found, skipping."

Actual behaviour

Claude Code fails to start entirely. The tool is non-functional until the stale entry is manually removed from the settings file.

Context

This was triggered by a prior session that added a project-specific additionalDirectories entry (a tender working directory). When that directory was later deleted, Claude Code would not start on the next launch.

Fix required scrubbing the entry from settings.local.json with a Python script to restore functionality.

Environment

• Platform: macOS (Darwin 25.2.0)
• Shell: zsh

Suggested fix

Validate additionalDirectories entries on startup; skip any that do not exist with a warning rather than hard-failing.