Accepted formats: Plain text or Moodle-auto format. HTML tags and multi-lang tags are also accepted, as well as the following placeholders:
<ul>
<li>Course name {$a->coursename}</li>
<li>Link to user's profile page {$a->profileurl}</li>
<li>User email {$a->email}</li>
<li>User fullname {$a->fullname}</li>
<li>User first name {$a->firstname}</li>
<li>User last name {$a->lastname}</li>
<li>User course role {$a->courserole}</li>
</ul>