diff --git a/src/fgai/monitor.py b/src/fgai/monitor.py
index 8c5efcf..e8d7d4c 100644
--- a/src/fgai/monitor.py
+++ b/src/fgai/monitor.py
@@ -388,6 +388,11 @@ def cached_status_with_error(cache_path: str, error_status: dict[str, object]) -
             row.setdefault("raw_error", "")
             row.setdefault("aggregate_error", "")
             row.setdefault("error", row.get("aggregate_error") or row.get("raw_error") or "")
+            if row.get("aggregate_status") == "error" and not row.get("aggregate_error") and row.get("error"):
+                row["aggregate_error"] = str(row.get("error", ""))
+            if row.get("partial") and not row.get("raw_error") and row.get("error"):
+                row["raw_error"] = str(row.get("error", ""))
+    cached["status_schema"] = 2
     cached["generated_at"] = int(time.time())
     cached["stale"] = True
     cached["stale_reason"] = "live_mcp_error"
diff --git a/tests/test_monitor.py b/tests/test_monitor.py
index 9819d6c..ca4f6ab 100644
--- a/tests/test_monitor.py
+++ b/tests/test_monitor.py
@@ -119,7 +119,7 @@ class MonitorTests(unittest.TestCase):
                 {
                     "summary": {"total": 42},
                     "capabilities": {"graylog_mcp": {"status": "connected"}},
-                    "stream_coverage": [{"stream_name": "Firewall", "aggregate_status": "error"}],
+                    "stream_coverage": [{"stream_name": "Firewall", "aggregate_status": "error", "error": "old aggregate error"}],
                     "cross_source_correlations": [{"entity": "10.0.0.1"}],
                 },
             )
@@ -128,10 +128,11 @@ class MonitorTests(unittest.TestCase):
 
             self.assertIsNotNone(status)
             self.assertEqual(status["summary"]["total"], 42)
+            self.assertEqual(status["status_schema"], 2)
             self.assertTrue(status["stale"])
             self.assertEqual(status["capabilities"]["graylog_mcp"]["status"], "error")
             self.assertTrue(status["status_cache"]["served_from_cache"])
-            self.assertEqual(status["stream_coverage"][0]["aggregate_error"], "")
+            self.assertEqual(status["stream_coverage"][0]["aggregate_error"], "old aggregate error")
             self.assertEqual(status["stream_coverage"][0]["raw_error"], "")