A young brahmin, sixteen years old, well versed in the Vedas, and with his head shaven. He was "of good stock, well informed, a good speaker and a scholar of ability." He visited the Buddha at Opasāda, where he interrupted a conversation which the Buddha was holding with some aged brahmins; they rebuked him for interrupting his elders, but Cankī, who happened to arrive at that moment, interceded on his behalf. The Buddha, knowing that Kāpathika had questions to ask of him, gave him an opportunity for so doing, and there followed a discussion on various points, detailed in the Cankī Sutta. At the end of the discussion the youth declared himself a disciple of the Buddha (M.ii.168ff).
In the Sutta the Buddha addresses Kāpathika as Bhāradvāja, perhaps because he belonged to that gotta.