Please lead with the location of the position and include the keywords INTERN, REMOTE, or H1B if the corresponding sort of candidate is welcome. Feel free to post any job that may interest HN readers from executive assistant to machine learning expert to CTO.
Please also see: "Ask HN: Freelancer? Seeking freelancer?" (May 2012) http://news.ycombinator.com/item?id=3914001
For example, if I am looking for H1B opportunities, ctl+f finds basically every listing because those who aren't willing to accept H1B say, "no H1B". If you don't accept these candidates, the convention assumes that by default. Don't explicitly say it.