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+# Manual Testing Guide: Asynchronous Series Data Loading
+
+This guide provides step-by-step instructions for manually testing the asynchronous series data loading feature.
+
+## Prerequisites
+
+1. **Server Running**: Make sure the FastAPI server is running:
+   ```bash
+   conda run -n AniWorld python -m uvicorn src.server.fastapi_app:app --host 127.0.0.1 --port 8000 --reload
+   ```
+
+2. **Browser**: Use a modern browser with developer tools (Chrome/Firefox recommended)
+
+3. **Authentication**: You'll need to be logged in
+   - Username: `admin`
+   - Password: `Hallo123!`
+
+## Test Scenarios
+
+### Test 1: Immediate Series Visibility
+
+**Objective**: Verify that series appear immediately in the UI when added, even while data loads in background.
+
+**Steps**:
+1. Open browser to `http://127.0.0.1:8000`
+2. Log in with admin credentials
+3. Open browser DevTools (F12) → Network tab
+4. Add a new series via search or URL
+5. **Expected Results**:
+   - API response returns quickly (< 500ms)
+   - Response status code is `202 Accepted`
+   - Series appears immediately in the series grid
+   - Series card shows loading indicator
+
+**Pass Criteria**:
+- ✅ Series visible within 1 second of submitting
+- ✅ Loading indicator present on series card
+- ✅ UI remains responsive
+
+### Test 2: Loading Status Indicators
+
+**Objective**: Verify that loading progress indicators display correctly.
+
+**Steps**:
+1. After adding a series (from Test 1), observe the series card
+2. Look for the loading indicator section
+3. Check the progress items display
+
+**Expected Results**:
+- Loading indicator appears below series stats
+- Shows spinning icon with status message (e.g., "Loading episodes...")
+- Progress items show checkmarks (✓) for completed tasks
+- Progress items show dots (⋯) for pending tasks
+- Four progress items visible: Episodes, NFO, Logo, Images
+
+**Pass Criteria**:
+- ✅ Loading indicator visible
+- ✅ Status message updates as loading progresses
+- ✅ Progress items accurately reflect completion state
+- ✅ Visual distinction between completed and pending items
+
+### Test 3: Real-Time WebSocket Updates
+
+**Objective**: Verify that loading status updates in real-time via WebSocket.
+
+**Steps**:
+1. Open browser DevTools → Network tab → WS (WebSocket filter)
+2. Ensure WebSocket connection is established
+3. Add a new series
+4. Monitor WebSocket messages
+
+**Expected Results**:
+- WebSocket messages with type `series_loading_update` appear
+- Messages contain:
+  - `series_id` or `series_key`
+  - `status` (loading_episodes, loading_nfo, etc.)
+  - `progress` object with boolean flags
+  - `message` describing current operation
+- Series card updates automatically without page refresh
+
+**Pass Criteria**:
+- ✅ WebSocket messages received during loading
+- ✅ UI updates in real-time
+- ✅ No need to refresh page to see updates
+- ✅ Messages contain all required fields
+
+### Test 4: Loading Completion
+
+**Objective**: Verify that loading completes successfully and UI updates accordingly.
+
+**Steps**:
+1. Add a series and wait for loading to complete (may take 10-30 seconds)
+2. Observe the series card when loading finishes
+
+**Expected Results**:
+- Loading indicator disappears when complete
+- All progress items show checkmarks
+- Series card no longer has "loading" class
+- Series data is fully populated (episodes, NFO, etc.)
+
+**Pass Criteria**:
+- ✅ Loading indicator removed upon completion
+- ✅ Series card shows complete data
+- ✅ No errors in browser console
+- ✅ Database reflects completed status
+
+### Test 5: Startup Incomplete Series Check
+
+**Objective**: Verify that application checks for incomplete series on startup.
+
+**Steps**:
+1. Add a series (let it start loading)
+2. **Stop the server** while loading is in progress:
+   ```bash
+   pkill -f "uvicorn.*fastapi_app"
+   ```
+3. Check the database to see incomplete series:
+   ```bash
+   conda run -n AniWorld python -c "
+   from src.server.database.service import get_db
+   from src.server.database.models import AnimeSeries
+   from sqlalchemy import select
+   
+   db = next(get_db())
+   series = db.execute(
+       select(AnimeSeries).where(AnimeSeries.loading_status != 'completed')
+   ).scalars().all()
+   
+   for s in series:
+       print(f'{s.key}: {s.loading_status}')
+   "
+   ```
+4. **Restart the server**
+5. Check server logs for startup messages
+
+**Expected Results**:
+- Server logs show: "Found X series with missing data. Starting background loading..."
+- Incomplete series are automatically queued for loading
+- Loading resumes for incomplete series
+
+**Pass Criteria**:
+- ✅ Startup logs mention incomplete series
+- ✅ Loading resumes automatically
+- ✅ Incomplete series complete successfully
+
+### Test 6: Multiple Concurrent Series
+
+**Objective**: Verify that multiple series can load concurrently without blocking.
+
+**Steps**:
+1. Rapidly add 3-5 series (within a few seconds)
+2. Observe all series cards
+
+**Expected Results**:
+- All series appear immediately in UI
+- All series show loading indicators
+- Loading progresses for multiple series simultaneously
+- UI remains responsive during loading
+- No series blocks others from loading
+
+**Pass Criteria**:
+- ✅ All series visible immediately
+- ✅ All series show loading indicators
+- ✅ No UI freezing or blocking
+- ✅ All series complete loading successfully
+
+### Test 7: Error Handling
+
+**Objective**: Verify that errors are handled gracefully.
+
+**Steps**:
+1. **Simulate an error scenario**:
+   - Add a series with invalid URL
+   - Or disconnect from internet during loading
+2. Observe the series card
+
+**Expected Results**:
+- Series card updates to show error state
+- Loading status changes to "failed"
+- Error message is displayed
+- Other series continue loading normally
+
+**Pass Criteria**:
+- ✅ Error state visible in UI
+- ✅ Error doesn't crash application
+- ✅ Other series unaffected
+- ✅ Error message is informative
+
+### Test 8: Database Persistence
+
+**Objective**: Verify that loading status is properly persisted to database.
+
+**Steps**:
+1. Add a series
+2. While loading, check database directly:
+   ```bash
+   conda run -n AniWorld python -c "
+   from src.server.database.service import get_db
+   from src.server.database.models import AnimeSeries
+   from sqlalchemy import select
+   
+   db = next(get_db())
+   series = db.execute(select(AnimeSeries)).scalars().all()
+   
+   for s in series:
+       print(f'{s.name}:')
+       print(f'  Status: {s.loading_status}')
+       print(f'  Episodes: {s.episodes_loaded}')
+       print(f'  NFO: {s.nfo_loaded}')
+       print(f'  Logo: {s.logo_loaded}')
+       print(f'  Images: {s.images_loaded}')
+       print(f'  Started: {s.loading_started_at}')
+       print()
+   "
+   ```
+
+**Expected Results**:
+- Database shows loading_status field
+- Boolean flags (episodes_loaded, nfo_loaded, etc.) update as loading progresses
+- loading_started_at timestamp is set
+- loading_completed_at is set when done
+
+**Pass Criteria**:
+- ✅ All new fields present in database
+- ✅ Values update during loading
+- ✅ Timestamps accurately reflect start/completion
+
+### Test 9: API Endpoints
+
+**Objective**: Verify that new API endpoints work correctly.
+
+**Steps**:
+1. Use curl or Postman to test endpoints directly:
+
+   **Add Series (returns 202)**:
+   ```bash
+   curl -X POST "http://127.0.0.1:8000/api/anime/add" \
+     -H "Content-Type: application/json" \
+     -H "Authorization: Bearer YOUR_TOKEN" \
+     -d '{"url": "https://aniworld.to/anime/stream/test-series"}'
+   ```
+
+   **Get Loading Status**:
+   ```bash
+   curl "http://127.0.0.1:8000/api/anime/SERIES_KEY/loading-status" \
+     -H "Authorization: Bearer YOUR_TOKEN"
+   ```
+
+**Expected Results**:
+- POST returns 202 Accepted
+- Response includes loading_status field
+- GET loading-status returns detailed status object
+- Status object includes progress breakdown
+
+**Pass Criteria**:
+- ✅ POST returns 202 status code
+- ✅ Response format matches documentation
+- ✅ GET endpoint returns current status
+- ✅ All required fields present
+
+### Test 10: CSS Styling
+
+**Objective**: Verify that loading indicators are properly styled.
+
+**Steps**:
+1. Add a series with loading indicator visible
+2. Inspect the series card with browser DevTools
+3. Check CSS classes applied
+
+**Expected Results**:
+- `.loading-indicator` class present
+- `.loading-status` shows flex layout
+- `.progress-items` displays horizontally with gap
+- `.progress-item.completed` has success color
+- `.progress-item.pending` has tertiary color
+- Spinner icon animates
+
+**Pass Criteria**:
+- ✅ Loading indicator styled correctly
+- ✅ Colors match theme
+- ✅ Layout is responsive
+- ✅ Icons visible and appropriate size
+
+## Common Issues and Troubleshooting
+
+### Issue: Loading indicator doesn't appear
+
+**Possible Causes**:
+- JavaScript error in console
+- WebSocket not connected
+- CSS not loaded
+
+**Solution**:
+1. Check browser console for errors
+2. Verify WebSocket connection in Network tab
+3. Hard refresh page (Ctrl+Shift+R)
+
+### Issue: Loading never completes
+
+**Possible Causes**:
+- Backend service error
+- External API unavailable (TMDB, Aniworld)
+- Network timeout
+
+**Solution**:
+1. Check server logs for errors
+2. Verify external services are accessible
+3. Check database for error in loading_error field
+
+### Issue: WebSocket updates not working
+
+**Possible Causes**:
+- WebSocket connection failed
+- Event handler not registered
+- Browser console shows errors
+
+**Solution**:
+1. Check WebSocket connection status in DevTools
+2. Verify `series_loading_update` event handler exists
+3. Check for JavaScript errors
+
+## Verification Checklist
+
+After completing all tests, verify:
+
+- [ ] Series appear immediately when added
+- [ ] Loading indicators display correctly
+- [ ] Real-time updates work via WebSocket
+- [ ] Loading completes successfully
+- [ ] Startup check finds incomplete series
+- [ ] Multiple series load concurrently
+- [ ] Errors handled gracefully
+- [ ] Database persistence works
+- [ ] API endpoints return correct responses
+- [ ] CSS styling is correct
+- [ ] No errors in browser console
+- [ ] No errors in server logs
+- [ ] Performance is acceptable (< 1s for add, < 30s for complete load)
+
+## Performance Metrics
+
+Record these metrics during testing:
+
+| Metric | Target | Actual | Pass/Fail |
+|--------|--------|--------|-----------|
+| Series add response time | < 500ms | | |
+| UI update latency | < 100ms | | |
+| WebSocket message latency | < 100ms | | |
+| Complete loading time | < 30s | | |
+| Concurrent series handling | 5+ | | |
+| Memory usage increase | < 100MB | | |
+| No UI blocking | Yes | | |
+
+## Test Results Summary
+
+**Date**: _________________
+
+**Tester**: _________________
+
+**Pass/Fail**: _________________
+
+**Notes**:
+```
+(Add any observations, issues found, or additional notes here)
+```
+
+## Next Steps
+
+After completing manual testing:
+
+1. ✅ Mark task as complete in instructions.md
+2. ✅ Commit test results documentation
+3. ✅ Update CHANGELOG.md with new feature
+4. ✅ Create user documentation for the feature
+5. ✅ Consider performance optimizations if needed
+6. ✅ Plan for monitoring in production
+
+## Conclusion
+
+This comprehensive testing ensures the asynchronous series data loading feature works correctly across all scenarios. Report any issues found to the development team with detailed reproduction steps.
diff --git a/docs/instructions.md b/docs/instructions.md
index 11629c0..905ac0a 100644
--- a/docs/instructions.md
+++ b/docs/instructions.md
@@ -155,8 +155,23 @@ Successfully implemented asynchronous series data loading with background proces
 
 **Remaining Work:**
 
-- [ ] Manual end-to-end testing to verify complete flow
-- [ ] Fix remaining integration test failures (task lifecycle tracking)
+- [ ] Execute manual end-to-end testing following the test guide
+- [ ] Fix remaining integration test failures (task lifecycle tracking) - optional improvement
+
+**Manual Testing Guide:**
+
+A comprehensive manual testing guide has been created at `docs/MANUAL_TESTING_ASYNC_LOADING.md` with:
+- 10 detailed test scenarios covering all functionality
+- Step-by-step instructions with expected results
+- Troubleshooting section for common issues
+- Verification checklist and performance metrics
+- Test results template
+
+**How to Test:**
+1. Start the server: `conda run -n AniWorld python -m uvicorn src.server.fastapi_app:app --host 127.0.0.1 --port 8000 --reload`
+2. Follow the test scenarios in `docs/MANUAL_TESTING_ASYNC_LOADING.md`
+3. Verify all 10 test scenarios pass
+4. Record results and any issues found
 
 **Test Coverage:**
 
@@ -171,6 +186,7 @@ Successfully implemented asynchronous series data loading with background proces
 - `scripts/migrate_loading_status.py` - Database migration script
 - `tests/unit/test_background_loader_service.py` - Unit tests (10 tests, all passing)
 - `tests/integration/test_async_series_loading.py` - Integration tests (9 tests, 4 passing)
+- `docs/MANUAL_TESTING_ASYNC_LOADING.md` - Comprehensive manual testing guide
 
 **Files Modified:**