How exactly does a CalDAV server advertise Tasks support?
<p>After connecting to a CalDAV server, you can query to see which services it supports.  For example, after Lightning connects to a CalDAV server, it will only allow you to create Task objects if that server advertises Task support.</p>

<p>Unfortunately, some servers (e.g. AppSuite, Yahoo) do support Tasks, but apparently do not correctly advertise the fact, and so strict PIM clients (e.g. Lightning) will not talk Tasks with them.</p>

<p>How (exactly) should CalDAV do this?</p>

<p>I have read <a href="https://wiki.wocommunity.org/display/~probert/CalDAV+and+CardDAV+handshake" rel="nofollow">https://wiki.wocommunity.org/display/~probert/CalDAV+and+CardDAV+handshake</a> which explains the CalDAV handshake and connectivity, and identifies the DAV features list returned by the OPTIONS call after connecting.  Our CalDAV server returns the following list:
<code>
1, 2, 3, access-control, calendar-access, addressbook, extended-mkcol, calendar-auto-schedule, calendar-schedule, calendarserver-sharing, calendarserver-principal-search, calendarserver-principal-property-search, calendarserver-private-comments, extended-mkcol, calendar-managed-attachments
</code></p>

<p>However, I cannot find anywhere an exhaustive list of standard feature names, nor can I find out which name is expected for Tasks to be supported.</p>

<p>Can anyone shed some light on this?</p>