Malformed additionalDirectories entry in settings.json causes silent failure (zero output, exit 0)

Summary

A non-path string (HTML content) in ~/.claude/settings.json permissions.additionalDirectories causes Claude Code 2.1.63+ to silently produce zero output. No error message, no stderr, exit code 0.

Versions affected

• Works: 2.1.62 and below (tolerates the malformed entry)
• Broken: 2.1.63 through 2.1.69 (silent failure, zero output)

Root cause

The additionalDirectories array in ~/.claude/settings.json contained a string that was HTML content rather than a filesystem path. Example:

"additionalDirectories": [
  "/valid/path/one",
  "/Users/me/Projects/SomeProject/Heres what I think this deck should look like. The goal is: <b>Read this and know exactly what to implement.</b></p>\n\n<p><b>Slide 1: Title</b>...",
  "/valid/path/two"
]

A ~500 character string containing HTML tags, line breaks, and presentation content got concatenated with a directory path and saved to settings.

(This was added during a Claude session where It asked for permission and I obviously didn't notice in enough detail what it was adding. )

How to reproduce

1. Add any non-path string containing HTML to additionalDirectories in ~/.claude/settings.json
2. Run claude -p "hello" in terminal
3. Observe: zero output, no error, exit code 0

Expected behavior

Claude Code should:

1. Validate additionalDirectories entries are plausible filesystem paths
2. Skip or warn about invalid entries rather than silently failing
3. At minimum, produce an error message — not zero output with exit 0

How it likely happened (secondary bug)

During a Claude Code session, I was working with HTML content (presentation instructions). When Claude Code prompted for directory access approval, the HTML content was somehow concatenated into the path string and auto-saved to settings.json. Claude Code should sanitize directory paths before persisting them to settings.

Debugging notes

• Version bisect confirmed 2.1.62 → 2.1.63 is the breaking point
• The async init refactor in 2.1.63 (sync j8(() => { → async T8(async () => {) appears to be where the tolerance for malformed entries was lost
• Removing ~/.claude/settings.json entirely and letting it regenerate fixes the issue
• Removing only the HTML blob from additionalDirectories fixes the issue
• Re-adding the HTML blob reproduces the failure — confirmed multiple times

Workaround

Remove the malformed entry from ~/.claude/settings.json permissions.additionalDirectories. If Claude Code produces zero output after an update, try mv ~/.claude/settings.json ~/.claude/settings.json.bak and test again.

Environment

• macOS Sequoia (Darwin 24.6.0)
• Node 22.x via nvm
• Claude Code installed via npm