Google announced during Google I/O 2025 that it’s rolling out Project Mariner, the company’s experimental AI agent that browses and uses websites, to more users and developers. Google also says it’s significantly updated how Project Mariner works, allowing the agent to take on nearly a dozen tasks at a time.

U.S. subscribers to Google’s new $249.99-per-month AI Ultra plan will get access to Project Mariner, and the company says support for more countries is coming soon. Google also says it’s bringing Project Mariner’s capabilities to the Gemini API and Vertex AI, allowing developers to build out applications powered by the agent.

First unveiled in late 2024, Project Mariner represents Google’s boldest effort yet to revamp how users interact with the internet through AI agents. At launch, Google Search leaders said they viewed Project Mariner as part of a fundamental user experience shift, in which people will delegate more tasks to an AI agent, instead of visiting websites and completing those tasks themselves.

For example, Project Mariner users can purchase tickets to a baseball game or buy groceries online without ever visiting a third-party website — they just chat with Google’s AI agent, and it visits websites and takes actions for the