I have Prometheus alert , I need node Name in the labels

- alert: example-alert
      annotations:
        description: Memory on node currently at % 
          is under pressure
        summary: Memory usage is under pressure, system may become unstable.
      expr: |
        100 - ((node_memory_MemAvailable_bytes{job="node-exporter"} * 100) / node_memory_MemTotal_bytes{job="node-exporter"}) > 50
      for: 2m
      labels:
        nodeName: 
        severity: warning

{endpoint="metrics",instance="172.16.17.100:9100",job="node-exporter",namespace="monitoring",pod="mypromoperator-prometheus-node-exporter-gg5nl",service="mypromoperator-prometheus-node-exporter"} 67.09431138997289
{endpoint="metrics",instance="172.16.17.101:9100",job="node-exporter",namespace="monitoring",pod="mypromoperator-prometheus-node-exporter-9mfn2",service="mypromoperator-prometheus-node-exporter"} 52.7483247365166e

but want to see node name n the query , how to configure alert so that I will get node name

https://github.com/rajendar38/prometheus