Researchers tracked 112 professional developers using AI agents on the job and found they plan tasks, review every diff, and limit agent scope rather than handing off vague prompts. In trials, AI slowed senior devs by 19% and produced merged PRs only 8% of the time, revealing a 92% failure rate when agents ran unsupervised.

• Study of 112 pro developers found they treat AI agents like junior devs—scoping tasks tightly, reviewing every diff, and stepping in for cross-system or ambiguous work rather than vibe coding.
• In one trial, experienced open-source maintainers using AI were actually 19% slower.
• An agent connected to an issue tracker only got its PRs merged 8% of the time—a 92% failure rate when run with less supervision.
• The "hands-off swarm of agents" demos popular on social media don't match how real production code gets shipped.