Requirements

Plugin code must be idempotent.
Do not copy modules from fuel-library. Add the module path into task description instead and use fuel-library as framework: puppet_modules: "puppet/modules:/etc/puppet/modules"
If you use plugin pre-deployment scripts that somehow change the state of the Fuel Master node -- for example, changes to Nailgun database --ensure that all these changes are removed in the post-deployment script.
See code-style and Fuel contribution guidelines
recommendation on pre_build_hook