Clever

Thor smiled. His son was hanging off Clint's every word, sharp green eyes taking in everything the archer did, occasionally asking questions that Clint happily answered.

"He's clever," Loki said. Thor glanced at his brother. "He looks, he listens, and he absorbs information. While he isn't quite the intellect that Hermione is, nor the same sort of information sponge, he does react well and quickly when called upon to do so." He laid a hand on Thor's shoulder. "He will pass this test, brother. And it is a necessary test to put him through."

—- Chapter 7, First Impressions