[BUG]

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?

--resume always forks the session

When using claude --resume, selecting a session creates a new
session file instead of continuing in the original. This causes session duplication
over time.

Same behaviour with claude --continue.

What Should Happen?

picker should not create a new session, unless --fork-session is specified.

Error Messages/Logs

Steps to Reproduce

1. claude --resume
2. see there are n sessions to pick from
3. select one
4. exit
5. claude --resume
6. see there are (n+1) sessions to pick from

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.51 (Claude Code)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

_No response_