Another endorsement of CivWillard here. In addition to managing research agreements, it also can be configured to show you in one place how much gold every other civ has, who you are eligible for a research agreement with (based on gold etc), what resources civs have available for trade, what resources of yours they will trade for, what city focus each of your cities has (including ability to change it from a single location), a list of all City States with every civ who is protecting them, current ally, your current influence...
Basically, take a whole bunch of data that you need but is almost impossible to get just because of convoluted UI and put it all in one simple and easy to use presentation.