An MCP Server Card is a static metadata document that describes a remote MCP server well enough for a client to discover and connect to it. Domain-level discovery goes through /.well-known/ai-catalog.json, whose entries point to the cards.
MCP Server Cards
An MCP Server Card is a static metadata document that describes a remote MCP server well enough for a client to discover and connect to it. Domain-level discovery goes through /.well-known/ai-catalog.json, whose entries point to the cards.
Where it stands
As of 2026-10-13, the Agentic Standards Map records:
Experimental extension of MCP: the README of the extension repository still reads “not an accepted or official MCP extension” (2026-10-13). SEP-2127 (PR #2127, “MCP Server Cards - HTTP Server Discovery”, Extensions Track) was merged on 2026-10-06 (14:43 UTC, merge commit 0a11bf6) by a maintainer of the MCP repository; the Specification Enhancement Proposal (SEP) file, read 2026-10-13, carries “Status: Final” and says the full extension specification stays in the extension repository, graduating to a repository named ext-server-card on acceptance. …
Why it matters to agents
A Server Card is “a static metadata document that describes a remote MCP server enough for clients to discover and connect to it”; cards “intentionally omit primitive listings (tools, resources, prompts)”. docs/discovery.md says clients performing domain-level discovery SHOULD attempt to retrieve /.well-known/ai-catalog.json, whose entries of type application/mcp-server-card+json point to the cards. …
Sources
- https://modelcontextprotocol.io/community/working-groups/server-card
- https://aaif.io/projects
- https://github.com/modelcontextprotocol/ext-server-card
- https://github.com/modelcontextprotocol/ext-server-card/blob/main/docs/discovery.md
- https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2127
- https://github.com/modelcontextprotocol/ext-server-card/pull/47
Status and relevance quoted, shortened, from the Agentic Standards Map by Francesco Marinoni Moretto, CC BY 4.0, https://frmoretto.github.io/agentic-standards-map/. The full entry, with every dated source, is in map.json under mcp-server-card.
Industry: cross-domain
Related standards
Standards this one builds on, supersedes, profiles or is commonly deployed beside.
