Code completion (inline suggestion)
Real-time, ghost-text proposals of the next tokens, lines or blocks, shown as the developer types and accepted with a keystroke.
Code completion is the original AI coding product surface. The model receives the file prefix (and often suffix and neighbouring files) and proposes a continuation. Because it fires hundreds of times a day, small acceptance rates still add up: Google reports 37% acceptance and that 50% of code characters at the company are AI-completed. Completions are cheap and low-risk per suggestion, which is why adoption spread faster than for agents.