[BUG] Sending a message to a subagent send the message twice

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?

If you have a subagent running, and you swap to it and send a message, the message is sent twice.

What Should Happen?

It should only send the message to the subagent once.

Error Messages/Logs

Steps to Reproduce

1. Start a job with subagents
2. At the bottom when you have the choice between - main and - [subagent], choose the subagent
3. Send a message to the subagent

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.214

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_