What WebMCP enables
WebMCP makes website functions directly callable by agents in the browser. A website can offer product search or cart changes as described JavaScript tools. The agent receives structured inputs and results for functions it would otherwise use through the visible interface.
Connections with other protocols
- WebMCP exposes tools within a loaded website. An MCP server offers tools through a separate connection between client and server.
- The tools call website functions and use their connection to the merchant system, for example for search or cart operations.
Versions and licence
- Published version
- No separate version stated
- Working draft
- Draft Community Group Report dated 20 October 2026
Explicitly not a W3C Standard and not on the W3C Standards Track. Chrome documents an Origin Trial starting with Chrome 149.
- Licence / terms
- Specification: W3C Community Contributor License Agreement (CLA); check implementations separately.
Licence and terms ↗
An example flow
- A website registers a product search tool and describes the accepted inputs.
- A browser supporting WebMCP makes the tool available to the agent.
- The agent passes a search term and filters to the tool.
- The website runs the search and returns the result to the agent.
SDKs and examples
These libraries and examples help you get started. Each entry lists the language, package and supported version.
The specification and reference project provide a starting point for your own implementation.
Practical integration
- The current text is a Draft Community Group Report dated 20 October 2026. Chrome documents testing through an Origin Trial starting with version 149.
- The website registers its tools in the browser context. Its normal user interface can remain available alongside them.