Fielding stats are among the hardest to quantify, but the Astros usually do a good job of not kicking the baseball around. They are tied for seventh with the Cubs, Royals and Mariners with 73 errors this season. I’d say they are above-average defensively as a team.
Agreed on fielding stats, but fielding percentage might be the least relevant. FanGraphs has them at 23rd in defensive runs saved, well below average.
Watching today’s game, I stand corrected. The Astros have been shooting themselves in the foot defensively since July 30. They have the second most errors during that timeframe.