Autonomy Is Earned per Action, Not per Agent METR's 2025 randomized trial found 16 experienced open-source developers took 19% longer on 246 real tasks when AI was allowed, with time shifting from writing into prompting, waiting and reviewing, according to the article's account of the study. Klarna said in February 2024 its AI assistant handled 2.3 million conversations in a month, the workload of 700 full-time agents, and estimated a $40 million profit improvement, but by May 2025 CEO Sebastian Siemiatkowski told Bloomberg the company was hiring human agents again after cost-dominated evaluation and falling quality. The piece argues autonomy should be granted per action class rather than per agent, separating reliability, trust, autonomy, authorization and accountability, and treating human review as temporary support retired as evidence accumulates. Agents can now produce actions faster than people can responsibly verify them. The closest measurement is not an agent study but one of AI-assisted coding: in METR's 2025 randomized trial, 16 experienced open-source developers took 19% longer on 246 real tasks when AI was allowed.