Modules
MCP authorization discovery and its server-side URL guard.
How a client learns where a remote MCP server's authorization lives, the way the MCP authorization spec says
The one rule for a URL fetched server-side: https, a real hostname, and
nothing that resolves into the cluster. OAuth clients, MCP discovery and
dynamic client registration all GET/POST tenant-supplied addresses from
inside the platform, which is exactly the request an SSRF wants — so every
one of them passes through check/1 first, and again on each use, since DNS
can change between a save and a fetch.