When enterprise-managed policy blocks an MCP server, the resulting error now carries a structured reason attached via a new nnn(...) call, rather than a generic denial. The error message itself also now wraps the server name with a formatting helper (yr), as in "MCP server ${yr(Et)} is blocked by enterprise managed policy".
MCP enterprise-policy block errors now carry a reason
An MCP server blocked by enterprise policy now carries a structured reason on the error.
Under the hoodTier: how much it should matter to you
2Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
MCPArea: what it touches
Internal ChangesKind: in v2.1.257,
Internal ChangesSection of the release