When trying to use the kubernetes agent block i am presented with the error:

 
WorkflowScript: 14: Invalid agent type "kubernetes" specified. Must be one of [any, docker, dockerfile, label, none] @ line 14, column 1.
kubernetes {

I am using Jenkins version: 2.107.3 and kubernetes-plugin version: 1.12.2

I have searched but the only advice seems to be that the use of kubernetes in agent blocks requires Jenkins 2.66+