Jonathan Dingel on Friday stumbled upon a Preferential Trade Agreements Database hosted by the McGill University Faculty of Law which contains the text, or link to the text, of multiple PTAs.
Given the abundance of studies that use trade activity as a direct (or proxy) measure for openness, this is an incredible collection that makes quantification of relevant and actual treaty information relatively straightforward (assuming one already knows what they are coding). While PTAs are only a portion of all that is trade liberalization, a compilation of such knowledge is incredibly useful.
A good find!