According to Zach Buchanan on Twitter, the deal is quite a cheap one by major-league terms, with Matt Reynolds making a base salary of $675,000, and a $25,000 bonus if he appears in 55 games this year. Given the major-league minimum salary is likely to be a little above $500,000, he's not making much more than that, especially considering this is his second year of arb-eligibility. However, he did miss a lot of playing time during The Summer of Tommy John which the Diamondbacks "enjoyed", costing him the entire 2014 season, with his debut this year not coming until August 23.
There was speculation Reynolds could be a non-tender candidate, as his 4.61 ERA was unimpressive. Reynolds was particularly vulnerable to the long ball, allowing six in just 13.2 innings of work [for comparison, Brad Ziegler and Andrew Chafin combined to give up six HR over their 143 innings]. Probably the most notable was the grand-slam he gave up to Miguel Montero (above), though he did have a good strike-out rate, fanning 18. Right now, it's not clear if there will be room for him in the bullpen, with most of the slots already apparently allocated: right now, I'd be thinking Ziegler, Hudson, Bracho, Hernandez, Chafin, Collmenter, Delgado
However, if the team wants to go with a pair of left-handed relievers, it's possible room could be found for Reynolds. Although, in that department, there's still also the possibility of adding Oliver Perez, who is a free-agent. Hell, we might as well resign Joe Thatcher and Tony Sipp from the Astros too, put the whole band back together... The settlement leaves the Diamondbacks with seven arbitration players left: Collmenter, Welington Castillo, Patrick Corbin, Delgado, Hudson, Rubby De La Rosa and A.J. Pollock