add note about auth restricting MCP server generation

Author: ethanpalm

mcp.mdx

@@ -8,9 +8,13 @@ icon: 'audio-waveform'
 
 The Model Context Protocol (MCP) is an open protocol that connects your functions to LLMs and AI applications. With Mintlify's integration, you can automatically generate an MCP server from your existing documentation or OpenAPI specifications, enabling seamless AI-powered interactions with your product.
 
-## Quick usage guide
+<Note>
+  MCP servers can only be generated for public documentation. Documentation behind end-user authentication cannot be accessed for server generation.
+</Note>
 
-Any public documentation hosted on Mintlify can be extracted as an MCP server using the following command:
+## Generating your MCP server
+
+Public documentation hosted on Mintlify can be extracted as an MCP server using the following command:
 
 ```bash
 npx mint-mcp add <your-subdomain-or-domain>