[BUG] /resume does not find sessions by custom title (/rename) or auto-generated slug

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

## Summary
The /resume command fails to find sessions when given either:

1. The custom title set via /rename
2. The auto-generated slug (e.g. immutable-wandering-breeze)

It returns: Session [name] was not found.

## Environment

• Platform: Windows 11
• Claude Code version: 2.1.101
• Shell: bash (via Claude Code CLI)

What Should Happen?

## Expected Behavior
/resume <name> should match sessions by:

• Custom title set via /rename (customTitle field in the .jsonl)
• Auto-generated slug (slug field in the .jsonl)

## Actual Behavior
Returns Session [name] was not found. for both.

## Workaround
Resuming by full session UUID works:
/resume e503316c-f952-4a64-9d0a-63f61b99203a

Error Messages/Logs

Steps to Reproduce

1. Start a session and use /rename creating-cron to give it a custom title
2. In a new session, run /resume creating-cron → not found
3. Also tried the auto-generated slug (visible in the .jsonl file under the slug field) → also not found

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.101

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

<img width="1419" height="539" alt="Image" src="https://github.com/user-attachments/assets/2b6282ab-f5aa-4b13-b660-3836bc39c555" />
<img width="1431" height="577" alt="Image" src="https://github.com/user-attachments/assets/5c6868ff-5665-4dd6-afc5-54faee520fe0" />