The validation cartridge lets you apply FreeMarker templates to the localized messages, allowing messages to contain contextual data from the bean context, as well as data about the actual rule failure. You must prefix FreeMarker-based messages with ftl: and reference the contextual data using standard FreeMarker notation. The beans from the bean context can be referenced directly, while you can refer to the RuleEvalResult and rule failure path through the ruleResult and path beans.

Here is an example that uses RegexProvider rules which shows how Smooks can be used to perform validation of message fragment data:

customerId=ftl:Invalid customer number '${ruleResult.text}' at '${path}'.  Customer number must match pattern '${ruleResult.pattern}'.