The v1.0 release of the official MCP C# SDK introduces icon support for tools, resources, and prompts. Icons can be added via the IconSource attribute parameter for simple cases, or through McpServerToolCreateOptions.Icons for advanced scenarios supporting light/dark themes, size hints, and MIME types. The Implementation class
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Because a picture is worth a thousand wordsThe simple case: a single icon via attributeThe advanced case: multiple icons with metadataServer and client identity iconsTips for choosing iconsSeeing it in actionMore informationSort: