Also sign Jake Fox and Caleb Gindl.
No reason to overreact to a minor league signing but getting Wilton Lopez on one seems pretty solid.
He was a very good reliever for three years in Houston before getting traded to Colorado. Really good GB and BB rates, good enough but not great K rates.
2.8 fWAR from 2010-2012, and he even worked as a closer for a bit.
His first year in Colorado his PD stats dipped a bit but he was still effective (0.8 WAR; DIPS around 3.60)
In 2014 the Rockies demoted him after 6.1 bad innings. He posted a 3.77 FIP in AAA.
His velocity dipped in 2014 but the sample size is tiny, and I think he had surgery to remove loose bodies while in the minors.
As the bullpen currently stands, he'd be the 3rd best projected reliever behind Loup and Cecil (3.79 FIP).