That's right. If you want to add some documentations bits about the tooling we can help you with the GIT stuff, but you need to at least write the docs using the docbook format that is plain XML. You can take a look at the docs files in the repo that Esteban mention. More specifically here:
https://github.com/droolsjbpm/jbpm/tree/master/jbpm-docs/src/main/docbook/en-US
We don't want to slow down your contributions so we can help you with the administrative part if you provide content :)
Cheers