If you add a title property to the anchor tag you will get a tooltip which will be read by screen-readers and displayed visually when the user hovers with the mouse over the link. If you really want to hide this tooltip from the sighted you can code two links, one with the title attribute and one without, and then use a screen CSS to hide the link with title and an aural CSS to hide the link without title. I'm not sure if there's a more efficient way of doing this with HTML5 since I haven't done any web development in the last 10 years.

You're in luck. It can be done in markdown. You can add the title property anyway. Add it after the URL, still within the paranthesis, enclosed in quotes, seperated from the URL by a space. Here is an example:

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The title is likely the best solution. Whats the particular information you want to give to screenreaders? Extra description or some easter eggs for the blind readers? I don't see any visual stuff in your links that would need extra description.

Perhaps the `role` attribute?

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