diff --git a/apps/api/src/services/alert_rule_engine.py b/apps/api/src/services/alert_rule_engine.py
index 25033e20f..7b96173ab 100644
--- a/apps/api/src/services/alert_rule_engine.py
+++ b/apps/api/src/services/alert_rule_engine.py
@@ -7,7 +7,7 @@ OpenClaw 告警規則匹配引擎
 - 規則在 YAML 定義，不需要改 Python 代碼
 - 匹配邏輯: alertname 完全匹配 > alert_type 部分匹配 > message 關鍵字
 - priority 越小越優先，999 = 通用兜底
-- 變數替換: {target} {host} {container} {instance} {job} {namespace}
+- 變數替換: {target} {host} {container} {instance} {job} {namespace} {unit}
 
 自動規則生成:
 - 只有 generic_fallback 觸發時才生成（具體規則不觸發）
@@ -185,6 +185,7 @@ def _extract_vars(alert_context: dict) -> dict[str, str]:
     host = instance.split(":")[0] if ":" in instance else instance
     job = labels.get("job", "exporter")
     namespace = alert_context.get("namespace", "awoooi-prod")
+    unit = labels.get("unit", "")
 
     # GAP-A4: 多層 label 查找，由最權威到最弱
     target = ""
@@ -245,6 +246,7 @@ def _extract_vars(alert_context: dict) -> dict[str, str]:
         "instance": instance,
         "job": job,
         "namespace": namespace,
+        "unit": unit,
     }
 
 
diff --git a/apps/api/src/services/incident_service.py b/apps/api/src/services/incident_service.py
index ab97b2cad..bcf463a70 100644
--- a/apps/api/src/services/incident_service.py
+++ b/apps/api/src/services/incident_service.py
@@ -116,7 +116,7 @@ def classify_alert_early(
     1. ConfigurationDrift / KubeConfigDrift → TYPE-4D (Config Drift 卡片)
     2. severity=info/none → TYPE-1 (純資訊，無按鈕)
     3. backup/heartbeat 關鍵字 → TYPE-1（但 backup failure age > 24h → TYPE-3，見下）
-    4. Docker/Host 前綴 → infrastructure TYPE-3
+    4. Docker/Host/Systemd runner 前綴 → infrastructure/host_resource TYPE-3
     5. Kube/Pod/Deploy/Node/Velero/ArgoCD 前綴 → kubernetes TYPE-3
     6. Postgres/Redis 前綴 → database TYPE-3
     7. 預設 → general TYPE-3
@@ -183,6 +183,12 @@ def classify_alert_early(
     if severity in ("info", "none"):
         return "info", "TYPE-1"
 
+    # 2026-05-05 ogt + Codex: self-hosted runners are host-level systemd services.
+    # Must run before the generic "watchdog" heartbeat rule because
+    # SystemdRunnerWatchdogEnabled contains "Watchdog" but is not a heartbeat.
+    if alertname.startswith("SystemdRunner"):
+        return "host_resource", "TYPE-3"
+
     # 5. Backup / Heartbeat — 純資訊，不進 LLM
     # HostBackupFailed 必須在 Host prefix 前攔截，否則被歸 host_resource/TYPE-3
     # 2026-04-12 ogt: 只針對已知主機備份監控 alertname，不用寬泛關鍵字
diff --git a/apps/api/tests/test_classify_alert_early.py b/apps/api/tests/test_classify_alert_early.py
index e1008ebe3..c4f133d2d 100644
--- a/apps/api/tests/test_classify_alert_early.py
+++ b/apps/api/tests/test_classify_alert_early.py
@@ -12,8 +12,8 @@ classify_alert_early() 分類函數單元測試 — ADR-073 Phase 2-2 + ADR-075
 """
 
 import pytest
-from src.services.incident_service import classify_alert_early
 
+from src.services.incident_service import classify_alert_early
 
 # --------------------------------------------------------------------------- #
 # TYPE-4D: Config Drift
@@ -110,6 +110,16 @@ class TestInfrastructure:
         ac, nt = classify_alert_early("HostOutOfDiskSpace", "warning", {})
         assert ac == "host_resource"
 
+    @pytest.mark.parametrize("alertname", [
+        "SystemdRunnerRestartSpike",
+        "SystemdRunnerWatchdogEnabled",
+        "SystemdRunnerMissingResourceQuota",
+    ])
+    def test_systemd_runner_is_host_resource_not_heartbeat(self, alertname):
+        ac, nt = classify_alert_early(alertname, "warning", {})
+        assert nt == "TYPE-3"
+        assert ac == "host_resource"
+
 
 # --------------------------------------------------------------------------- #
 # ADR-075: alertchain_health (TYPE-8M)
diff --git a/apps/api/tests/test_gap_a4_placeholder_resolution.py b/apps/api/tests/test_gap_a4_placeholder_resolution.py
index e70f0093a..a468e35c0 100644
--- a/apps/api/tests/test_gap_a4_placeholder_resolution.py
+++ b/apps/api/tests/test_gap_a4_placeholder_resolution.py
@@ -25,7 +25,6 @@ from src.services.alert_rule_engine import (
     match_rule,
 )
 
-
 # =============================================================================
 # _strip_pod_suffix
 # =============================================================================
@@ -158,6 +157,20 @@ class TestExtractVarsGapA4:
         }
         assert _extract_vars(ctx)["target"] == "awoooi-web"
 
+    def test_systemd_unit_label_extracted_for_host_rule_templates(self):
+        """Systemd runner alert labels must fill {unit} in SSH diagnostics."""
+        ctx = {
+            "target_resource": "SystemdRunnerWatchdogEnabled",
+            "labels": {
+                "alertname": "SystemdRunnerWatchdogEnabled",
+                "instance": "192.168.0.110:9100",
+                "unit": "actions.runner.owenhytsai-awoooi.awoooi-110.service",
+            },
+            "namespace": "awoooi-prod",
+        }
+        vars = _extract_vars(ctx)
+        assert vars["unit"] == "actions.runner.owenhytsai-awoooi.awoooi-110.service"
+
 
 # =============================================================================
 # match_rule 後置驗證 — 最後一道防線
@@ -205,3 +218,25 @@ class TestMatchRuleRejection:
             assert "awoooi-api" in result["kubectl_command"]
             assert "unknown" not in result["kubectl_command"]
             assert "KubePodCrashLooping" not in result["kubectl_command"]
+
+    def test_systemd_runner_rule_preserves_unit_ssh_command(self):
+        """SystemdRunner* must keep a filled read-only SSH diagnostic command."""
+        ctx = {
+            "alert_type": "infrastructure",
+            "severity": "warning",
+            "source": "prometheus",
+            "target_resource": "SystemdRunnerWatchdogEnabled",
+            "namespace": "awoooi-prod",
+            "message": "runner watchdog enabled",
+            "labels": {
+                "alertname": "SystemdRunnerWatchdogEnabled",
+                "instance": "192.168.0.110:9100",
+                "unit": "actions.runner.owenhytsai-awoooi.awoooi-110.service",
+            },
+        }
+        result = match_rule(ctx)
+        assert result is not None
+        assert result["rule_id"] == "systemd_runner_baseline_alert"
+        assert result["kubectl_command"].startswith("ssh 192.168.0.110 ")
+        assert "actions.runner.owenhytsai-awoooi.awoooi-110.service" in result["kubectl_command"]
+        assert "{unit}" not in result["kubectl_command"]
diff --git a/apps/api/tests/test_golden_regression.py b/apps/api/tests/test_golden_regression.py
index 64253397a..acccb8488 100644
--- a/apps/api/tests/test_golden_regression.py
+++ b/apps/api/tests/test_golden_regression.py
@@ -10,7 +10,6 @@
 """
 from __future__ import annotations
 
-import pytest
 from src.services.incident_service import classify_alert_early
 
 
@@ -49,6 +48,10 @@ class TestHostResource:
         cat, ntype = classify_alert_early("HostDiskSpaceFull", "critical")
         assert cat == "host_resource" and ntype == "TYPE-3"
 
+    def test_systemd_runner_watchdog_is_not_heartbeat(self):
+        cat, ntype = classify_alert_early("SystemdRunnerWatchdogEnabled", "warning")
+        assert cat == "host_resource" and ntype == "TYPE-3"
+
 
 class TestHighCpuVariants:
     """HighCPU* prefix 規則覆蓋"""