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Adds movie ratings and number of voters to links on IMDB. Modified version of http://userscripts.org/scripts/show/96884
< Opiniones de Add movie ratings to IMDB links [adopted]
Possibly.
The Rotten Tomatoes API does not appear to be very open.
However there may be alternatives.
I just know that this and this script use the same API: https://www.rottentomatoes.com/api/private/v2.0/search/ - it's key-less and works much better than the OMDb API (see my comment).
Here is some description.
It would be so good if you could add RT rating either. Do you think it's possible?