MCP proposals: server cards lean on AI Catalog, trust labels move to extensions
Two open MCP proposals moved in the past weeks. In the discussion of SEP-2127 (MCP Server Cards, metadata a client can read before it connects), a comment on 24 September said the server card is not at a generic well-known address and needs an AI Catalog to point to it. SEP-1913 (trust and sensitivity annotations) is being split into small extensions in an experimental repository, and its refined design reserves an optional evidenceRef field that carries a digest, a canonicalization and a schema so a reader can check the record it points to. Both proposals are still open.
Discovery before connection looks set to run through a catalog that points to an MCP-specific card, so owners who publish server metadata should follow where the card ends up. evidenceRef moves claims about a server toward records a client can verify by digest instead of taking on trust.
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