diff --git a/src/core/main.py b/src/core/main.py
index 9c9019438..8abb08682 100644
--- a/src/core/main.py
+++ b/src/core/main.py
@@ -2126,19 +2126,56 @@ def _sync_creatives_impl(
                                             f"url={bool(data.get('url'))}, "
                                             f"width={data.get('width')}, "
                                             f"height={data.get('height')}, "
-                                            f"variants={len(preview_result.get('previews', [])) if preview_result else 0}"
+                                            f"variants={len(preview_result.get('previews', []))}"
                                         )
+                                    else:
+                                        # Preview generation failed for update - creative is invalid
+                                        error_msg = f"Creative validation failed: preview_creative returned no previews for update of {existing_creative.creative_id}"
+                                        logger.error(f"[sync_creatives] {error_msg}")
+                                        failed_creatives.append(
+                                            {
+                                                "creative_id": existing_creative.creative_id,
+                                                "error": error_msg,
+                                                "format": creative_format,
+                                            }
+                                        )
+                                        failed_count += 1
+                                        results.append(
+                                            SyncCreativeResult(
+                                                creative_id=existing_creative.creative_id,
+                                                action="failed",
+                                                errors=[error_msg],
+                                            )
+                                        )
+                                        continue  # Skip this creative update
 
                                 except Exception as validation_error:
-                                    # Creative agent validation failed for update - log warning but continue
-                                    # This allows updates even if creative agent is down
-                                    error_msg = f"Creative agent validation failed: {str(validation_error)}"
-                                    logger.warning(
-                                        f"[sync_creatives] {error_msg} for update of {existing_creative.creative_id} - continuing with update",
+                                    # Creative agent validation failed for update (network error, agent down, etc.)
+                                    # Do NOT update the creative - it needs validation before acceptance
+                                    error_msg = (
+                                        f"Creative agent unreachable or validation error: {str(validation_error)}. "
+                                        f"Retry recommended - creative agent may be temporarily unavailable."
+                                    )
+                                    logger.error(
+                                        f"[sync_creatives] {error_msg} for update of {existing_creative.creative_id}",
                                         exc_info=True,
                                     )
-                                    # Note: We continue instead of failing to allow graceful degradation
-                                    # when creative agent is unavailable
+                                    failed_creatives.append(
+                                        {
+                                            "creative_id": existing_creative.creative_id,
+                                            "error": error_msg,
+                                            "format": creative_format,
+                                        }
+                                    )
+                                    failed_count += 1
+                                    results.append(
+                                        SyncCreativeResult(
+                                            creative_id=existing_creative.creative_id,
+                                            action="failed",
+                                            errors=[error_msg],
+                                        )
+                                    )
+                                    continue  # Skip this creative update
 
                             # In full upsert, consider all fields as changed
                             changes.extend(["url", "click_url", "width", "height", "duration"])
@@ -2389,24 +2426,61 @@ def _sync_creatives_impl(
                                             if dimensions.get("duration"):
                                                 data["duration"] = dimensions["duration"]
 
-                                    logger.info(
-                                        f"[sync_creatives] Preview data populated: "
-                                        f"url={bool(data.get('url'))}, "
-                                        f"width={data.get('width')}, "
-                                        f"height={data.get('height')}, "
-                                        f"variants={len(preview_result.get('previews', [])) if preview_result else 0}"
-                                    )
+                                        logger.info(
+                                            f"[sync_creatives] Preview data populated: "
+                                            f"url={bool(data.get('url'))}, "
+                                            f"width={data.get('width')}, "
+                                            f"height={data.get('height')}, "
+                                            f"variants={len(preview_result.get('previews', []))}"
+                                        )
+                                    else:
+                                        # Preview generation failed - creative is invalid
+                                        error_msg = f"Creative validation failed: preview_creative returned no previews for {creative_id}"
+                                        logger.error(f"[sync_creatives] {error_msg}")
+                                        failed_creatives.append(
+                                            {
+                                                "creative_id": creative_id,
+                                                "error": error_msg,
+                                                "format": creative_format,
+                                            }
+                                        )
+                                        failed_count += 1
+                                        results.append(
+                                            SyncCreativeResult(
+                                                creative_id=creative_id,
+                                                action="failed",
+                                                errors=[error_msg],
+                                            )
+                                        )
+                                        continue  # Skip this creative
 
                             except Exception as validation_error:
-                                # Creative agent validation failed - log warning but continue
-                                # This allows creatives to be stored even if creative agent is down
-                                error_msg = f"Creative agent validation failed: {str(validation_error)}"
-                                logger.warning(
-                                    f"[sync_creatives] {error_msg} - continuing with creative storage",
+                                # Creative agent validation failed (network error, agent down, etc.)
+                                # Do NOT store the creative - it needs validation before acceptance
+                                error_msg = (
+                                    f"Creative agent unreachable or validation error: {str(validation_error)}. "
+                                    f"Retry recommended - creative agent may be temporarily unavailable."
+                                )
+                                logger.error(
+                                    f"[sync_creatives] {error_msg} - rejecting creative {creative_id}",
                                     exc_info=True,
                                 )
-                                # Note: We continue instead of failing to allow graceful degradation
-                                # when creative agent is unavailable
+                                failed_creatives.append(
+                                    {
+                                        "creative_id": creative_id,
+                                        "error": error_msg,
+                                        "format": creative_format,
+                                    }
+                                )
+                                failed_count += 1
+                                results.append(
+                                    SyncCreativeResult(
+                                        creative_id=creative_id,
+                                        action="failed",
+                                        errors=[error_msg],
+                                    )
+                                )
+                                continue  # Skip storing this creative
 
                         # Determine creative status based on approval mode
 
diff --git a/templates/creative_management.html b/templates/creative_management.html
index 027b4c450..297681078 100644
--- a/templates/creative_management.html
+++ b/templates/creative_management.html
@@ -392,7 +392,7 @@ <h2 id="previewTitle" style="margin: 0 0 1.5rem 0;">Creative Preview</h2>
     .then(response => response.json())
     .then(data => {
         if (data.success) {
-            alert(`AI Review Complete:\n\nDecision: ${data.decision}\n\nReasoning: ${data.reasoning}`);
+            alert(`AI Review Complete:\n\nStatus: ${data.status}\n\nReason: ${data.reason}\n\nConfidence: ${data.confidence}`);
             window.location.reload();
         } else {
             alert('Error: ' + (data.error || 'Unknown error'));
@@ -496,8 +496,13 @@ <h3 style="margin: 0 0 0.5rem 0;">${creativeData.title || 'Native Ad'}</h3>
         }
     } else {
         html += `<div style="text-align: center; padding: 3rem; color: #999;">
-                    <p>No preview available for this creative.</p>
-                    <p style="font-size: 0.9rem; margin-top: 0.5rem;">Creative data: ${JSON.stringify(creativeData || {}, null, 2)}</p>
+                    <div style="font-size: 3rem; margin-bottom: 1rem;">🖼️</div>
+                    <h3 style="color: #666; margin-bottom: 0.5rem;">No Preview Available</h3>
+                    <p style="color: #999; margin-bottom: 1rem;">This creative doesn't have preview data yet.</p>
+                    <details style="text-align: left; max-width: 600px; margin: 0 auto; padding: 1rem; background: #f9fafb; border-radius: 8px;">
+                        <summary style="cursor: pointer; font-weight: 600; color: #666;">Show Creative Data</summary>
+                        <pre style="margin-top: 1rem; padding: 1rem; background: white; border-radius: 4px; overflow-x: auto; font-size: 0.85rem; text-align: left;">${JSON.stringify(creativeData || {}, null, 2)}</pre>
+                    </details>
                  </div>`;
     }