As it stands, genre blacklisting for the recent updates and frontpage is a planned feature that will be coming out sooner or later. I didn't feel like waiting any longer, so I wrote an userscript for filtering Yaoi and other tags, available at https://github.com/nuiva/Mangadex-filter.
I'm not sure about the API, but most Mangadex requests are capped at 600/10min. In other words, you may get banned if you somehow view tons of manga right after installing or spam the update cache button. The script caches tags, so later on it makes much less requests. Use it responsibly!
To clarify, the genre filter toggles are on the search page, but only affect the frontpage and updates page.
I'm not sure about the API, but most Mangadex requests are capped at 600/10min. In other words, you may get banned if you somehow view tons of manga right after installing or spam the update cache button. The script caches tags, so later on it makes much less requests. Use it responsibly!
To clarify, the genre filter toggles are on the search page, but only affect the frontpage and updates page.
