Google today announced an early preview of WebMCP, a new protocol that defines how AI agents interact with websites.

• “WebMCP aims to provide a standard way for exposing structured tools, ensuring AI agents can perform actions on your side with increased speed, reliability, and precision,” wrote André Cipriani Bandarra from Google.

WebMCP lets developers tell large language models exactly what each button or link on a website does. WebMCP allows websites to explicitly publish a clear “Tool Contract” that defines available actions.

It runs on a new browser API, navigator.modelContext. Through that API, the website shares a structured list of tools — such as buyTicket(destination, date). The AI can then call those functions directly, making interactions faster, more accurate, and far more reliable.

Structured interactions for the agentic web. WebMCP introduces two new APIs that let browser agents act on a user’s behalf:

• Declarative API: Handles standard actions defined directly in HTML forms.
• Imperative API: Supports complex, dynamic interactions that require JavaScript execution.

These APIs act as a bridge, making your website agent-ready. They enable faster, more reliable agent workflows than raw DOM manipulation.

Use cases. Google shared use cases that show how an AI agent can handle complex tasks for your users with speed and confidence:

• Travel: Users can get the exact flights they want. Agents can search, filter results, and complete bookings using structured data that delivers accurate results every time.
• Customer support: Users can create detailed support tickets faster. Agents can automatically fill in the required technical details.
• Ecommerce: Users can shop more efficiently. Agents can find products, configure options, and move through checkout with precision.

How to access the preview. You can apply for the preview to WebMCP here.

Why we care. Agentic experiences are shaping the future of search—and possibly SEO. Dan Petrovic called it the biggest shift in technical SEO since structured data. Glenn Gabe called this a big deal. It’s worth exploring these new protocols now.