[BUG] /heapdump fails on Windows with EEXIST when Desktop directory already exists

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?

Running the /heapdump slash command fails immediately with:

Failed to create heap dump: EEXIST: file already exists, mkdir 'C:\Users\<user>\Desktop'

The command attempts to mkdir the Desktop directory, which already exists on any normal Windows installation. It appears the heapdump logic doesn't use a recursive/{ recursive: true }
mkdir or doesn't check for directory existence before creating it.

What Should Happen?

/heapdump should successfully write a heap dump file to the Desktop (or another target directory), handling the case where the directory already exists.

Error Messages/Logs

Failed to create heap dump: EEXIST: file already exists, mkdir 'C:\Users\<user>\Desktop'

Steps to Reproduce

1. Open Claude Code on Windows (where ~/Desktop already exists)
2. Run /heapdump
3. Observe the EEXIST error

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.74

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

Likely fix: change fs.mkdirSync(desktopPath) to fs.mkdirSync(desktopPath, { recursive: true }), which is a no-op when the directory exists.