If you are talking about the jobdsl plugin:
What version of the jobdsl plugin do you use?
If you use 1.48+, if i recall correctly then you can use the autogenerated dsl documentation within your jenkins instance, further details:
https://github.com/jenkinsci/job-dsl-plugin/wiki/Automatically-Generated-DSL
Otherwise you might need to use the configure closure.
Cheers