/resume shows empty list despite valid sessions (--continue works)

This issue was written by Claude (Opus 4.5) during a debugging session with the user.

Bug Summary

/resume (and --resume) shows an empty session list for a specific project, while --continue successfully finds and resumes sessions in the same project.

What I'm certain about

1. The bug is reproducible: /resume consistently shows empty for this project
2. The data is correct: I (Claude) created a fresh project directory from scratch, and the sessions-index.json contains valid entries with correct projectPath and originalPath
3. --continue works: The same session that /resume can't find is successfully resumed with --continue
4. Inverted Ctrl+A behavior: When pressing Ctrl+A (show all projects), only the current project's sessions appear—the opposite of expected behavior

What I'm uncertain about

The root cause. Initial hypothesis was "paths containing spaces" but another project with spaces works fine. Something specific to this project triggers the bug.

Environment

• Claude Code version: 2.1.15
• Platform: macOS
• Project is a git submodule with spaces in the path

Reproduction

1. Fresh sessions-index.json created by Claude with valid entries
2. claude --continue → works, resumes the session
3. claude --resume → empty list
4. Ctrl+A in resume picker → shows only current project's sessions (should show all)

Ruled out

• Data corruption (Claude created fresh data, same issue)
• Dual npm/native installation (tested native-only, same issue)
• Manual index rebuild (same issue)

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>