Michael Intrator, co-founder and CEO of CoreWeave participates in an interview on the floor of the New York Stock Exchange in New York on Sept. 22, 2025. CoreWeave shares rose as much as 8% Wednesday as the artificial intelligence cloud provider announced new tools to help programmers develop AI agents. With the new serverless reinforcement learning service, there's no need to worry about adding or removing computing power, because it happens automatically. Tests indicated that when developers use CoreWeave's new service, they can train models faster with 40% lower costs in comparison with running Nvidia H100 graphics processing units locally, "with no impact on model quality," according to a statement. Reinforcement learning is a decades-old approach that involves evolving systems through trial and error to improve outcomes over time. The launch comes five months after CoreWeave paid $1 billion to acquire Weights and Biases, a startup targeting developers with software for training and evaluating AI models. The deal is an effort to complement CoreWeave's existing business of renting out Nvidia graphics processing units to companies that need infrastructure to operate models.