[BUG] MCP connection to Wolfram

### Preflight Checklist

- [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) 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?

Every time I start a new Claude Desktop session, I receive an error message: Error
Couldn't start for Cowork and Code sessions. Error: Connection closed.

The shared-pool proxy isn't handling the Wolfram MCP's stdio transport correctly for Cowork cloud sessions.
The MCP connection works fine in Chat, but fails in Cowork.

### What Should Happen?

[mcp-server-Wolfram.log](https://github.com/user-attachments/files/31864181/mcp-server-Wolfram.log)

### Error Messages/Logs

```shell
Error
Couldn't start for Cowork and Code sessions. Error: Connection closed.
```

### Steps to Reproduce

Start Mathematica, start Claude Desktop.

### Claude Model

_No response_

### Is this a regression?

Yes, this worked in a previous version

### Last Working Version

no idea

### Claude Code Version

Claude 1.46388.4 (50e62f) 2026-09-05T01:57:47.000Z

### Platform

Other

### Operating System

macOS

### Terminal/Shell

Other

### Additional Information

_No response_

Start with the attached mcp-server-Wolfram.log and reproduce the failure by starting Mathematica before Claude Desktop. Compare Chat with Cowork and Code sessions while investigating the shared-pool proxy's stdio transport; done means the Wolfram MCP connects without the “Connection closed” error in Cowork and Code.

Rédigé par le modèle d'indexation à partir du texte de l'issue.