Inserting item into a collection and auto generate slug value

Hi,

I have a collection named "Jobs" with a slug based on the title value like so

<perch:content id="title" type="text" label="Job Title" required="true" suppress="true" />
<perch:content id="jobSlug" for="title" type="slug" suppress="true" />

When inserting an item into this collection programmatically, i;e via an XML import, what are the rules for generating the slug value?

Many thanks