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 them.
Project Mariner competes with other web-browsing AI agents, such as OpenAI’s Operator, Amazon’s Nova Act, and Anthropic’s Computer Use. These tools are all in an experimental stage, and TechCrunch’s experience has proven the prototypes to be slow and prone to mistakes.
However, Google says it’s taken feedback from early testers to improve Project Mariner’s capabilities. A Google spokesperson tells TechCrunch the company updated Project Mariner to run on virtual machines in the cloud, much like agents from OpenAI and Amazon. This means users can work on other projects while Project Mariner completes tasks in the background — Google says the new Project Mariner can handle up to 10 tasks simultaneously.
This update makes Project Mariner significantly more useful compared to its predecessor, which ran on a user’s browser. As I noted in my initial review, Project Mariner’s early design meant users couldn’t use other tabs or apps on their desktop while the AI agent was working. This kind of defeated the purpose of an AI agent — it would work for you, but you couldn’t do anything else while it was working.
In the coming months, Google says users will be able to access Project Mariner in AI Mode, the company’s AI-powered Google Search experience. When it launches, the feature will be limited to Search Labs, Google’s opt-in testing ground for search features. Google says it’s working with Ticketmaster, StubHub, Resy, and Vagaro to power some of these agentic flows.
Separately today, Google unveiled an early demo of another agentic experience called “Agent Mode.” The company says this feature combines web browsing with research features and integrations, as well as with other Google apps. Google says Ultra subscribers will gain access to Agent Mode on desktop soon.
At this year’s I/O, Google finally seems willing to ship the agentic experiences it’s been talking about for years. Project Mariner, Agent Mode, and AI Mode all seem poised to change how users navigate the web, and how vendors interact with their customers online. Web-browsing agents have big implications for the internet economy, but Google seems ready to put all these agents out in the world.