[BUG] Windows: Claude Code calls cygpath when running bash commands, fails without Cygwin

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?

Environment

OS: Windows
CLI: Claude Code 2.1.29
Cygwin: not installed
Working dir: C:\GitHub\AEI (also happens in OneDrive path)
Steps to reproduce

Run Claude Code on Windows
Trigger any bash command
Error occurs

What Should Happen?

Expected
Claude Code should not require cygpath on Windows when Cygwin isn’t installed.

Error Messages/Logs

Steps to Reproduce

ERROR Command failed: cygpath -u 'c:\github\aei'

node:internal/errors:985:15

• genericNodeError (node:internal/errors:985:15)
• wrappedFn (node:internal/errors:539:14)
• checkExecSyncError (node:child_process:925:11)
• execSync (node:child_process:997:15)
• ev (file:///C:/Users/joe/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:22:261)
• WI (file:///C:/Users/joe/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:67:408)
• R9q (file:///C:/Users/joe/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:5212:7106)
• BQ (file:///C:/Users/joe/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:5212:10125)
• (file:///C:/Users/joe/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:5212:9894)
• at Array.some (<anonymous>)

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

1.2.29

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_