James Standard Mailets contains more than 50 matchers and mailets. MailetDocs is used to generate a catalog with reports on each mailet and matcher (for example HasHeader).
Setting up this report is easy. Just add the plugin to the reporting section. For example:
<reporting>
<plugins>
<plugin>
<groupId>org.apache.james</groupId>
<artifactId>maven-mailetdocs-plugin</artifactId>
<version>0.1</version>
</plugin>
...