Requirements from @toby:

• Goal is to allow private entries into an MCP registry
• Users who auth into an MCP registry should be able to see different available MCP servers based on what permissions they have
• Should be equal to (or at least similar) to how auth in the MCP spec works

Toby says Harald from VS Code and others can provide feedback, etc, to help nail down requirements here.

This would not be functionality we expose in the public registry - it'd just be a spec that downstream sub-registries can (optionally) adopt.