What is an MCP Server Card?
We request /.well-known/mcp.json and require a JSON content-type and a body that starts with a brace.
What it is
The Model Context Protocol is a convention for describing tools an agent can call: what each one does, what it takes and what it returns. A server card is the JSON document that advertises yours.
Publishing it at /.well-known/mcp.json is how an agent finds the card without being told where to look. Nothing forces the address, but it is the one clients try.
We require the response to be JSON, not just a 200. A catch-all route that answers every path with your HTML shell does not earn a Pass here.
Why an agent needs it
If you have a booking system, a stock lookup or a quote calculator, a card makes it callable instead of clickable.
Most small business sites expose no tools, and this Check stays a Warning at Low priority for them. It costs little today and matters as soon as you have an API worth calling.
The Fix
If you expose a tool an agent could usefully call, publish a server card at /.well-known/mcp.json with an application/json content-type.
Describe each tool in plain words, with its inputs and outputs, and state the authentication it needs. A tool an agent cannot authenticate against is a tool it cannot use.
If you expose nothing callable, leave this Warning where it is. It carries Low priority, and there is more to gain elsewhere in your Report.
This one is a change in your own markup or edge configuration, so the Fix Pack cannot write it for you. A Report names every page it affects, with the Evidence.