[BUG] claude auth login fails with socket closed unexpectedly after password change

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?

Version: 2.1.119
OS: macOS arm64 (Apple Silicon)
Error: Login failed: The socket connection was closed unexpectedly
Triggered by: Changed claude.ai password

Network diagnostics all pass:

• curl -I https://api.anthropic.com/v1/messages returns HTTP/2 405 (correct)
• TLS 1.3 handshake succeeds
• No proxy, no VPN, no firewall

Telemetry shows tengu_oauth_token_refresh_failure on every startup.
Clean reinstall of claude-code does not help.
rm -rf ~/.claude and reinstall does not help.
Issue persists for 8+ hours.

What Should Happen?

claude auth login should complete successfully and save credentials so Claude Code can connect to the API.

Error Messages/Logs

Steps to Reproduce

1. Change claude.ai account password (login via gmail).
2. Run: claude auth login
3. Browser opens, click Authorize
4. Browser shows "You're all set up for Claude Code"
5. Terminal shows: Login failed: The socket connection was closed unexpectedly
6. Claude Code is completely unusable - every startup shows tengu_oauth_token_refresh_failure

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude Code v2.1.119

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_