If I send a private message to a friend, and that message includes a link, Facebook automatically appends the site's icon, description, etc. to the message (assuming that site supports open graph).
However, when I use the Chat API to send that link to a friend, it doesn't do that. It just sends the link, but doesn't use the open graph information of the site to display image, description, etc.
Is there a way to fix that?
If you are planning to do this in PHP, I would recommend you to extend echo_facebook_client.php sample example which comes bundled with Jaxl library. This will let you send private message to a friend using your facebook application oauth tokens.
Last time when I checked facebook jabber documentation (which was a few months back), there was no official way to attach link metadata within a chat context. Under limitations section of the doc you will find:
Your client cannot send or receive HTML messages
