Update docs/toolhive/guides-registry/intro.mdx

Co-authored-by: Dan Barr <danbarr@users.noreply.github.com>

Author: rdimitrov

docs/toolhive/guides-registry/intro.mdx

@@ -118,7 +118,8 @@ The server supports five source types:
 
 1. **Managed** - A fully-managed MCP source
    - Ideal for hosting private MCP server catalogs
-   - Automatically exposes entries following the MCP Registry format
+   - Automatically exposes entries following the MCP Registry format with
+     ToolHive-specific extensions
    - Supports publishing MCP servers and skills via the `/v1/entries` admin API
 
 2. **Upstream API** - Sync from upstream MCP Registry APIs