A few weeks back I shipped Warden, a governance layer that sits in front of an MCP server and enforces who can read what. Role-based, field-level. The demo had a support role that could list customer accounts but never see their billing tier. The tier field is stripped from everything support gets back.

I was poking at it the way you poke at your own work when you don't quite trust it.. I tried this:

query_resource("accounts", {"tier": "Enterprise"})

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