The doc https://docs.openshift.com/container-platform/4.16/machine_management/creating_machinesets/creating-machineset-gcp.html#machineset-yaml-gcp_creating-machineset-gcp  gives Sample GCP MachineSet values
But there are some places are inconsistency.

1.
  name: <infrastructure_id>-w-a
      machine.openshift.io/cluster-api-machineset: <infrastructure_id>-w-a
        machine.openshift.io/cluster-api-machineset: <infrastructure_id>-w-a


I think it’s better to change <infrastructure_id>-w-a to <infrastructure_id>-worker-a, then it can keep consistent with the previous part


$ oc -n openshift-machine-api \
  -o jsonpath='{.spec.template.spec.providerSpec.value.disks[0].image}{"\n"}' \
  get machineset/<infrastructure_id>-worker-a

2.
      providerSpec:
        value:
          apiVersion: gcpprovider.openshift.io/v1beta1

Here gcpprovider.openshift.io/v1beta1 should be changed to machine.openshift.io/v1beta1, because I checked on a 4.16 GCP cluster, it shows machine.openshift.io/v1beta1 in the default machineset, not sure why here is gcpprovider.openshift.io/v1beta1 in the doc.

3.

2 For <node>, specify the node label to add.

Seems <node> should be changed to <role>, because it's <role> for 2 in the sample machineset values.  
        machine.openshift.io/cluster-api-machine-role: <role> 2 

    4.16

    1.
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