# Frontend Authentication Errors - Investigation

**Date:** 2026-01-31
**Issue:** Frontend showing 401/500 errors and WebSocket disconnections

---

## Error Summary

### Errors Observed:

1. **Health Check Timeout**
   ```
   127.0.0.1:8000/health:1 Failed to load resource: net::ERR_CONNECTION_TIMED_OUT
   ```

2. **API 401 Unauthorized**
   ```
   :8000/api/v1/projects:1 Failed to load resource: 401 (Unauthorized)
   ```

3. **Notifications 500 Error**
   ```
   :8000/api/v1/notifications/:1 Failed to load resource: 500 (Internal Server Error)
   ```

4. **WebSocket Reconnection Loop**
   ```
   [WebSocket] Authentication successful
   [WebSocket] Disconnected
   [WebSocket] Reconnecting in 1000ms (attempt 1)
   ```

---

## Root Causes

### 1. Backend Not Running
**Symptom:** Health check timeout on port 8000
**Cause:** Backend API server not started
**Fix:** Start backend services

### 2. Authentication Token Issue
**Symptom:** 401 on /api/v1/projects
**Cause:** Invalid or missing auth token
**Fix:** Check token storage and WorkOS configuration

### 3. Notifications Service Error
**Symptom:** 500 on /api/v1/notifications
**Cause:** Backend error in notifications endpoint
**Fix:** Check backend logs for stack trace

### 4. WebSocket Instability
**Symptom:** Connect → Auth → Disconnect loop
**Cause:** Backend disconnecting after authentication
**Fix:** Check WebSocket handler and auth middleware

---

## Investigation Steps

1. Check if backend is running
2. Check backend logs for errors
3. Verify WorkOS configuration
4. Check database connectivity
5. Review WebSocket handler code

---

## Next Steps

Run diagnostics to identify exact issue.
