sessions-index.json stops updating, breaking /resume and --resume

Description

The sessions-index.json file in ~/.claude/projects/<project>/ silently stops being updated, causing sessions to not appear in /resume or --resume. Session .jsonl files are still created and written to correctly on disk — only the index is stale.

Details

• Version: 2.1.37
• OS: macOS (Darwin 23.6.0)
• Index stopped updating: ~Feb 7, 2026
• Sessions in index: 58
• Actual session files on disk: 129
• Missing from resume: 71 sessions over ~2.5 weeks

The sessions-index.json had a com.apple.provenance extended attribute, though the file was writable. No lock files or other obvious blockers.

Reproduction

Not sure of the exact trigger. The index just stopped being written to at some point. Sessions continued to work normally (create, read, write) — only the index tracking was affected.

Workaround

Rebuilt the index manually by parsing all .jsonl session files and regenerating sessions-index.json. This restored all sessions to the resume list.

Expected Behavior

sessions-index.json should be updated every time a session is created or modified, so all sessions appear in /resume and --resume.

🤖 Generated with Claude Code