[BUG] Windows: IDE lockfile PID mismatch prevents Cursor detection

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?

The extension writes C:\Users\<you>\.claude\ide\<port>.lock, but pid in the lockfile doesn’t match the process actually listening on <port>.
In addition, IDE matching may be case-sensitive on Windows (d:\... vs D:\...), causing the CLI to ignore the lockfile.
Result: /ide shows No available IDEs detected in Cursor’s integrated terminal.

What Should Happen?

Running claude in Cursor’s integrated PowerShell terminal, then /ide, should list Cursor and allow connecting (or auto-connect if enabled).

What Actually Happens?

/ide shows: “No available IDEs detected…” even though Cursor + extension are running and the lockfile exists.

Error Messages/Logs

The lockfile contents (redacted token):
Path: C:\Users\<you>\.claude\ide\<port>.lock
Paste its JSON, but replace authToken with REDACTED.
Port is listening + who owns it:
Show that the port in <port>.lock is actually listening:
Get-NetTCPConnection -LocalPort <port>
Show OwningProcess PID.
PID mismatch proof:
Compare:
pid from lockfile vs OwningProcess from Get-NetTCPConnection.
Claude CLI version + Cursor version
Paste exact versions (claude --version, Cursor “About”).
Claude debug output (only relevant lines)
If you run with debug and see something like “failed to find executable” or “no lockfiles found”, include those lines.
Don’t paste huge logs; paste only sections mentioning: ide, lock, detect, cursor, mcp, spawn.

Steps to Reproduce

1)Open Cursor on Windows.
Ensure Claude Code extension is installed/enabled in Cursor.
Open Cursor integrated terminal (PowerShell).
cd into any workspace folder (example: D:\Cursor proj 1)
Run claude
In Claude, run /ide
Observe: No available IDEs detected
If it only happens in Cursor terminal but not Windows Terminal/Git Bash, say that explicitly.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.0.76

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Cursor

Additional Information

Powershell in cursor terminal, Possibly related / same symptom family: #5095, #5153, #13447, and the duplicate #14489.

<img width="526" height="597" alt="Image" src="https://github.com/user-attachments/assets/cb408403-fe18-458e-a834-2c2bdc43a844" />