Technology
Google and Microsoft propose WebMCP standard to connect AI agents directly to websites
The proposed WebMCP web standard allows websites to expose structured JavaScript tools to AI agents instead of relying on screen-scraping.
The short version
- Google and Microsoft have proposed WebMCP, a web draft allowing sites to expose structured tools directly to AI agents.
- The API enables AI agents to discover, query, and execute functions using JSON Schema within an open, authenticated browser tab.
- WebMCP is currently available as an experimental trial in Google Chrome.
- The standard is still a draft, with security models and broad cross-browser support yet to be finalized.
Key facts
- WebMCP is a W3C Web Machine Learning Community Group draft jointly developed by Google (Chrome) and Microsoft (Edge).[Hacker News]
- The proposed standard provides a JavaScript API for web pages to register structured tools that AI agents can discover, query using JSON Schema, and execute.[Hacker News]
- The API runs inside the user's open, authenticated browser tab and session rather than operating as a headless background process.[Hacker News]
- The API entry point moved from navigator.modelContext to document.modelContext, though a JavaScript shim can bridge both during the transition.[Hacker News]
- Security features for WebMCP include running tools visibly in the tab, origin isolation gated by a Permissions Policy, mandatory user consent dialogs for sensitive actions, and annotation hints for untrusted content.[Hacker News]
What remains uncertain
- WebMCP is a Community Group draft and is not yet on the official W3C standards track or standardized across other web browsers.[Hacker News]
- The long-term security model for WebMCP remains actively under development.[Hacker News]