Web Model Context Protocol · WebMCP API
WebMCP is an emerging standard that lets a site expose functions AI agents can use, beyond plain text content. It is a Draft Community Group Report of the W3C Web Machine Learning Community Group, not yet a W3C standard.
Standalone definition · 39 words
How does WebMCP work?
A page declares tools, meaning named, described and typed actions that an agent can call directly instead of crawling the interface or reading screenshots. The API relies on document.modelContext and its registerTool() method. WebMCP is not the MCP protocol: it is designed as a web platform API, with the notion of origin and browser permissions.
Where does the standard stand?
The document is published as a Draft Community Group Report, with editors from Microsoft and Google. It is not on the W3C standards track. An implementation exists in Chrome behind a test flag, and mainstream agents still rely mostly on reading the DOM and using the computer.
Should you care about it now?
For most sites, not as a priority. The basics of accessible actions (clear forms, explicit labels, semantic HTML) already serve agents. For a site with high-value actions (booking, quotes, purchase), WebMCP deserves monitoring and testing.
Frequently asked questions
Is WebMCP a W3C standard?
No. It is a Community Group draft, outside the formal standards track at this stage.
Does WebMCP replace MCP?
No. MCP connects models to server-side services. WebMCP exposes actions from the page, on the browser side.
Must a site implement WebMCP to be cited?
No. WebMCP concerns agent actions, not citation in answers.
Related terms
Further reading
- WebMCP : what is this new standard SEO/GEO for visibility in the LLM ?
- Google Search Central Live Paris recap: Google Is Betting big on Agentic Commerce
- ← Back to the GEO glossary (114 terms)