[BUG] Auto interaction between 2 Claude Code Desktop sessions

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?

I have 2 sessions coding on the same application and they used to be able to communicate to each other, but this seems to be broken after an upgrade, it seem like Claude is thinking, but nothing happens and when I suggest that it has overlooked a messages it says that it did not see it.

<img width="606" height="553" alt="Image" src="https://github.com/user-attachments/assets/59c17fa7-211c-4e4a-a895-d0184e8185fb" />

What Should Happen?

Claude should be able to communicate to its own session without manual interruption

Error Messages/Logs

Steps to Reproduce

Let sessions send messages to each other.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude 1.34493.1 (255293) 2026-08-21T02:05:20.000Z

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_