Rowland-Smith is coming off a disastrous year with the Mariners, posting a 6.75 ERA over 27 games, and allowing 141 hits in 109 1/3 innings. He also struck out just 49 while walking 44. In the face of declining peripherals and his first year of arbitration eligibility, the Mariners non-tendered him. He did have a sub-4 ERA in all three of his other years as an MLB pitcher.
With how much they prioritized him, it’s probably safe to say that the Astros view him as a legitimate piece to contend for a rotation spot. We shall see. He would bring another left arm to the Astros rotation, along with JA Happ, if he won the spot.
EDIT: Levine says it's a one-year deal, though the amount of money has not yet been revealed.
EDIT 2: Brian McTaggart of MLB.com is reporting that the deal is worth $725,000, plus incentives.