Factory Tool

Use the factorytool.xml import steps to include new types into the Plone Factory Tool  when creating new Archetypes content-types. This is needed because Archetypes needs the content to be already created before validating it. In order to avoid broken objects in the site, they're first created in a place called portal factory and moved to the desired place later after they've been validated.
Imagine you've created the Cat content-type and want to register a factory for it. Just create a factorytool.xml file for your extension profile with the following contents:

<?xml version="1.0"?>
<object name="portal_factory" meta_type="Plone Factory Tool">
  <factorytypes>
    <type portal_type="Cat"/>
  </factorytypes>
</object>

Check the Archetypes Developer Manual for more info about how to create content-types.