I'd like to build a FF add-on that overlays HN comments at the bottom of every page that's been discussed here. I really need some sort of search API for that,

I'd like to build a FF add-on that overlays HN comments at the bottom of every page that's been discussed here. I really need some sort of search API for that, otherwise the solution would be to do a fake-post of the article, just to see if anyone submitted it before, then delete it immediately if the submission succeeds.