For decades, we’ve built the web for human eyes. We design layouts, choose colors, and place buttons where people expect them. But in 2026, a new type of visitor has arrived: AI Agents. Until recently, these agents had to “squint” at our websites—taking screenshots and scraping messy HTML just to figure out how to book a flight or buy a shirt. That changed on February 10, 2026, when Google and Microsoft introduced the WebMCP (Web Model Context Protocol) preview.
Here is everything you need to know about the biggest shift in web architecture since the mobile revolution.
What is WebMCP?
WebMCP is a new browser standard that allows a website to speak directly to AI agents in a language they understand: Structured Code.
Instead of an AI agent guessing that a blue box is a “Search” button, WebMCP lets the website explicitly say: “I have a tool called search_products. It requires a category string and returns a list of items.”
The “USB-C” for the Web
Think of WebMCP as the browser-native version of Anthropic’s Model Context Protocol (MCP). While the original MCP connects AI to backend databases and local files, WebMCP lives in the frontend. It turns your browser tab into a “mini-server” that an AI can interact with securely and instantly.
The Two Ways to Build: Declarative vs. Imperative
WebMCP offers developers two distinct paths to make their sites “agent-ready.”
1. The Declarative API (No-Code/Low-Code)
This is for the quick wins. You can turn existing HTML forms into AI tools by simply adding a few attributes.
How it looks:
<form toolname="book_hotel" tooldescription="Search and book hotel rooms">
<input name="city" type="text" label="Destination City">
<input name="date" type="date" label="Check-in Date">
</form>Why it matters: AI agents can now “fill out” your forms without ever needing to look at the UI.
2. The Imperative API (JavaScript Power)
For complex apps (like Figma or Google Sheets), you can register dynamic JavaScript functions using the new navigator.modelContext API.
How it looks
navigator.modelContext.registerTool({
name: "apply_photo_filter",
description: "Applies a visual filter to the selected image",
execute: (args) => { /* Your complex JS logic here */ }
});Why it matters: This allows an AI to perform actions that don’t have a simple “submit” button, like adjusting a slider or editing a vector path.
Why Should You Care? (The “Agentic SEO” Era)
In 2026, traffic isn’t just coming from humans clicking links; it’s coming from agents acting on their behalf.
| Benefit | Impact |
| Reliability | Your site doesn’t break for AI agents just because you changed the button color or CSS layout. |
| Speed | One direct tool call is 89% more token-efficient than an AI trying to “read” your whole page via vision. |
| Conversion | If an agent can easily “Use” your site to complete a task, you become the preferred destination for AI-assisted shopping. |
Is it Secure?
One of the biggest concerns with WebMCP is “Agent Hijacking.” To prevent this, the W3C standard includes strict guardrails:
- User-in-the-loop: The browser will prompt the user before an agent can execute high-stakes tools (like
process_payment). - Same-Origin Policy: Agents only see tools registered by the site the user is currently visiting.
- Transient Scope: Once the user closes the tab, the tools vanish.
How to Get Started Today
WebMCP is currently in Early Preview (as of late February 2026).
- Chrome Canary: Download the latest Canary build and enable the
#web-mcpflag. - Audit Your Forms: Ensure your HTML forms have clear labels; these will be the first things your AI agents look for.
- Polyfill: Check out
@mcp-b/globalon npm to start testing the logic in browsers that don’t yet have native support.
Conclusion
The web is no longer just a collection of documents; it is becoming a collection of capabilities. By implementing WebMCP, you aren’t just updating your code—you are making your business “findable” and “usable” in the age of Agentic AI.