[BUG] Cursor Terminal very slow when running Claude Code if SSH passphrases are required

Environment

• Platform (select one):
• [X] Anthropic API
• [ ] AWS Bedrock
• [ ] Google Vertex AI
• [ ] Other: <!-- specify -->
• Claude CLI version: 1.0.30 (Claude Code)
• Operating System: macOS 15.4.1
• Terminal: Cursor IDE terminal

Bug Description

<!-- A clear and concise description of the bug -->
This only happens in a Cursor and VS Code terminal window. A regular MacOS terminal window does not have this problem.

When you have SSH keys that require a passphrase and you start a new terminal in Cursor or VS Code, and you properly add your passphrases as expected, then, when you type claude to start Claude Code, the command line is extremely slow - keystrokes disappear. When you hit Enter -> you can an SSH error message.

It seems like perhaps when you start Claude code a new terminal session is started and the need to enter passphrases is unhandled?

Steps to Reproduce

1. Setup 2 ssh keys that require passphrases (note: a lot of people don't have a passphrase on their SSH key, but we are required to)
2. In Cursor, startup a new terminal session - you will be prompted to enter the passphrase for each key. You should only need to enter the passphrase once.
3. Type claude at the terminal prompt - Claude code will start
4. Type /help. Only one or two key strokes will make it onto the screen - you type /help and you see l - the /he & p chars are not there.
5. Very slowly type each character to ensure it shows up on the screen - once you've got /help - type return to run the command
6. You'll see an output below that prompts you for your SSH passphrase again.

Expected Behavior

<!-- What you expected to happen -->
Claude code would respond to keystrokes - just like any command line interface.

Actual Behavior

<!-- What actually happened -->
Terminal is very slow - if you type one character every 3 to 5 seconds, it will make it to the screen. If you just hit enter at the Claude prompt - you'll get an error that the SSH passphrase is wrong.

Additional Context

<!-- Add any other context about the problem here, such as screenshots, logs, etc. -->

!Image

!Image

My .ssh/config file is set up correctly:

Host *.github.com
HostName github.com
User xxx
AddKeysToAgent yes
UseKeychain yes
IdentityFile ~/.ssh/id_xxxx