Auth: Frequent 403 'Request not allowed' requiring /login, persists after --resume

Bug Description

Frequently getting kicked out with a 403 error requiring manual /login to continue. The issue also persists when resuming previous conversations via --resume.

Error Message

API Error: 403 {"error":{"type":"forbidden","message":"Request not allowed"}} · Please run /login

Steps to Reproduce

1. Start a Claude Code session
2. After some time (or after network interruption), receive 403 error
3. Run /login to recover
4. When resuming an old conversation with --resume, the same 403 error appears even after logging in

Expected Behavior

• OAuth token should refresh automatically in the background without requiring manual /login
• Resuming a conversation (--resume) should not show a stale auth error if already authenticated

Actual Behavior

• Frequently logged out mid-session
• Resuming a previous conversation shows the 403 error as if still logged out
• Only /login command resolves the issue temporarily

Environment

• Claude Code version: 2.1.59
• OS: macOS (Darwin 25.3.0)
• Shell: zsh

Additional Context

This is a recurring issue that disrupts workflow. The --resume behavior is particularly confusing as the old conversation context carries a stale auth state even when the user has already re-authenticated.