From the 'help dtu' command in-game:

DTLs allow you to hear conversation among dragons. Please keep in mind that the dragonchatter you hear is your dragon hearing the conversations of other dragons. DTLs are provided to help you roleplay the part of your dragon. It's not IC to say that you as a rider can hear the chatter. Most riders can only hear their own dragon.

Below are the commands available thru the DTLs. Items in [brackets] are optional arguments.

dwho - what dragons are connected/listening
dwhere - where the other connected dragons are located
pair <rider|dragon> - who rides what dragon
pro all=<message> - send a message to all listening dragons
pro weyr=<message> - send a message to all listening dragons in your weyr.
pro wing=<message> - send a message to all listening dragons in your wing.
pro local=<message> - send a message to all listening dragons in the same room as your dragon.
pro <dragon>=<message> - send a message to a single dragon
pro <dragon> <dragon> <dragon>=<message> - send a message to multiple dragons.
pro <person>=<message> - send a message to a person. This does not tell the person what dragon projected the message. Don't abuse this! It's not IC to use a lot.
quiet on - prevents you from hearing the 'pro all' talk.
quiet off - cancels the 'pro all' block.
+wings - a list of who is in what wing
dtulist [color] - list of all dragons/riders by color. You can specify color.
think <message> - sends a message to your player-dragon, if you have one.
+dstats - some general statistics on you and your dragon

Other Key Points

  • As stated above, the DTL is your dragon hearing other dragon's conversations, not you hearing it directly as the rider. While you might certainly play that your lifemate is letting you in on his/her side of the chatter, keep in mind that it is IC to be able to filter; dragons and riders learn not to be constantly in the middle of each others' thoughts quite early on.
  • The DTL is an IC tool, not for OOC talk.
  • While RPing dragons in a particular area, please make certain you're using the correct command to bespeak only those dragons! Things can get awfully spammy for everyone else logged in if you're RPing dragons via the 'pro wing/weyr/all' commands, so please use your best judgement. Additionally, if there is 'pro all' chatter going on, the 'quiet on/off' command is at your disposal.
  • ICly, it is extremely rare for a dragon to bespeak anyone other than their rider. By book canon, an individual needed to be very well-known to both rider and dragon, H.A.D. (or deemed exceptional in some other sense, one such case being Master Robinton), or an emergency needed to be in play, in order for this to happen. This holds true on HT as well. Please keep in mind that it would likely be quite unsettling for someone un-Impressed to suddenly have a foreign voice intruding on their thoughts. Therefore, using 'pro <person>' should be used sparingly, and any RP dealing with communication between a dragon and someone other than their rider should be weighed with these facts - and any ICAs=ICCs - in mind.