{"version":"2.1.274","anchor":"mcp-config-sdk-server-type-now-rejected-outside-sdk-host-r","canonical_anchor":"mcp-config-sdk-server-type-now-rejected-outside-sdk-host-r","heading":"MCP config 'sdk' server type now rejected outside SDK host registration","tier":"notice","area":"MCP","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.274\/e\/mcp-config-sdk-server-type-now-rejected-outside-sdk-host-r","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.274","markdown":"### MCP config 'sdk' server type now rejected outside SDK host registration\n\nMCP servers of type 'sdk' in config files are now rejected unless registered by the SDK itself\n\n**What**\n\nAn MCP server declared with type `\"sdk\"` in a configuration file is now explicitly rejected with a dedicated error, unless the configuration comes from the in-process SDK (marked as source `dynamic`). The general \"unknown server type\" error message also no longer lists `sdk` as a valid type unless the source is `dynamic`.\n\n**Why**\n\nThis closes off a way of declaring an `sdk`-type server that only an SDK host application should be able to register, giving a clearer error instead of letting it fail as a generic unknown type.\n\n- Area: MCP\n- Names: `sdk`\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 1\/5"}