mcp-handler now has experimental support for WebMCP, the proposed web standard for exposing tools to in-browser agents. Add a single script tag to your site, and your existing MCP tools become available there too.
Opt tools in by adding them to the experimental_webMcp object:
Then load the script from your MCP endpoint with the ?webmcp-script parameter:
The script registers those tools with the page and proxies each call back to your MCP server as the signed-in user, so authenticated tools work without a browser-side OAuth flow.
Upgrade to mcp-handler@2.2.0 and read the documentation to get started.
source & further reading
vercel.com — original article
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