/rename without arguments still broken on resumed sessions (stale-closed #26686)

Bug

/rename without arguments fails with Could not generate a name: no conversation context yet even when there is
extensive conversation history. This happens consistently when resuming a session, and sometimes in active sessions too.

Steps to reproduce

1. Have a multi-turn conversation with Claude Code
2. End the session
3. Resume the session with --resume or --continue
4. Run /rename (no arguments)

Expected: Auto-generates a name from conversation context
Actual: Could not generate a name: no conversation context yet. Usage: /rename <name>

Environment

• Claude Code version: 2.1.123
• OS: macOS (Darwin 25.4.0, arm64)

Prior issues

This was previously reported in #26686 and #27668, both closed by the stale bot without a fix. The underlying bug
still exists.

Workaround

Passing a name explicitly (/rename my-name) works fine. Only the auto-generate (no-argument) form is broken.