Rudder

On the URL:
http://www.rudder-project.org/doc-4.1/_node_properties_expansion_in_directives.html

There is this text:

In any directive text field, you can access properties defined on nodes using the following syntax:

${node.properties[key_one][key_two]}

where:

• property_name is the name of the property defined via the API
• key_one and key_two are keys in the JSON structure

The "property_name" is not present in the example, nor anywhere on the Page.

It is probably simply missing from the example and should be:

${node.properties[property_name][key_one][key_two]}