Finding past Claude Code sessions by topic

Transcripts live in ~/.claude/projects/<cwd-slug>/<session-id>.jsonl (subagents under <id>/subagents/). In zsh, quote --include globs (--include="*.jsonl") or grep fails with "no matches found"; find . -name "*.jsonl" -exec grep -lis term {} + is more reliable. Rank candidates by keyword hit count, not just mtime: sessions that only mention a term in passing (e.g. in injected memory/context) show low counts, while the real session shows hundreds or thousands. Exclude the current session id, then parse user messages (type==user, skip strings starting with "<") to confirm and give the user claude --resume <id>.