diff --git a/hosts/aws/tyo0/services/prometheus.nix b/hosts/aws/tyo0/services/prometheus.nix
index 3218634..1ce8445 100644
--- a/hosts/aws/tyo0/services/prometheus.nix
+++ b/hosts/aws/tyo0/services/prometheus.nix
@@ -100,24 +100,44 @@ in
               alert = "NodeDown";
               expr = ''up{job="node_exporter"} == 0'';
               for = "5m";
+              annotations = {
+                summary = "Node exporter down on {{ $labels.instance }}";
+                description = "Node exporter on {{ $labels.instance }} has been down for more than 5 minutes.";
+              };
             }
             {
               alert = "HTTPDown";
               expr = ''up{job="blackbox_probe"} == 0 or probe_success{job="blackbox_probe"} == 0'';
               for = "5m";
+              annotations = {
+                summary = "HTTP probe failure on {{ $labels.instance }}";
+                description = "The HTTP blackbox probe on {{ $labels.instance }} has failed for more than 5 minutes.";
+              };
             }
             {
               alert = "MemoryFull";
               expr = ''node_memory_MemAvailable_bytes / node_memory_MemTotal_bytes < 0.1'';
               for = "5m";
+              annotations = {
+                summary = "Low available memory on {{ $labels.instance }}";
+                description = "{{ $labels.instance }} has less than 10% available memory for more than 5 minutes.";
+              };
             }
             {
               alert = "DiskFull";
               expr = ''node_filesystem_avail_bytes{mountpoint=~"/|/mnt"} / node_filesystem_size_bytes < 0.1'';
+              annotations = {
+                summary = "Low disk space on {{ $labels.instance }}";
+                description = "The disk {{ $labels.device }} mounted at {{ $labels.mountpoint }} on {{ $labels.instance }} has less than 10% of empty space available.";
+              };
             }
             {
               alert = "UnitFailed";
               expr = ''node_systemd_unit_state{state="failed"} == 1'';
+              annotations = {
+                summary = "Systemd unit {{ $labels.name }} failure on {{ $labels.instance }}";
+                description = "The systemd unit {{ $labels.name }} on {{ $labels.instance }} has entered a {{ $labels.state }} state.";
+              };
             }
           ];
         };
@@ -136,7 +156,26 @@ in
       configuration = {
         receivers = lib.singleton {
           name = "ntfy";
-          webhook_configs = lib.singleton { url = "https://ntfy.ny4.dev/alert"; };
+          webhook_configs = lib.singleton {
+            # https://docs.ntfy.sh/publish/#message-templating
+            url =
+              let
+                tmpl = lib.escapeURL ''
+                  {{ range .alerts }}- Status: {{ .status }}
+
+                    Labels:
+                    {{ range $k, $v := .labels }} - {{ $k }} = {{ $v }}
+                    {{ end }}
+                    Annotations:
+                    {{ range $k, $v := .annotations }} - {{ $k }} = {{ $v }}
+                    {{ end }}
+                    Source: {{ .generatorURL }}
+
+                  {{ end }}
+                '';
+              in
+              "https://ntfy.ny4.dev/alert?tpl=yes&md=yes&m=${tmpl}";
+          };
         };
         route = {
           receiver = "ntfy";