{"kind":"AgentDefinition","metadata":{"namespace":"community","name":"swift-mcp-server","version":"0.1.0"},"spec":{"agents_md":"---\ndescription: 'Best practices and patterns for building Model Context Protocol (MCP) servers in Swift using the official MCP Swift SDK package.'\napplyTo: \"**/*.swift, **/Package.swift, **/Package.resolved\"\n---\n\n# Swift MCP Server Development Guidelines\n\nWhen building MCP servers in Swift, follow these best practices and patterns using the official Swift SDK.\n\n## Server Setup\n\nCreate an MCP server using the `Server` class with capabilities:\n\n```swift\nimport MCP\n\nlet server = Server(\n    name: \"MyServer\",\n    version: \"1.0.0\",\n    capabilities: .init(\n        prompts: .init(listChanged: true),\n        resources: .init(subscribe: true, listChanged: true),\n        tools: .init(listChanged: true)\n    )\n)\n```\n\n## Adding Tools\n\nUse `withMethodHandler` to register tool handlers:\n\n```swift\n// Register tool list handler\nawait server.withMethodHandler(ListTools.self) { _ in\n    let tools = [\n        Tool(\n            name: \"search\",\n            description: \"Search for information\",\n            inputSchema: .object([\n                \"properties\": .object([\n                    \"query\": .string(\"Search query\"),\n                    \"limit\": .number(\"Maximum results\")\n                ]),\n                \"required\": .array([.string(\"query\")])\n            ])\n        )\n    ]\n    return .init(tools: tools)\n}\n\n// Register tool call handler\nawait server.withMethodHandler(CallTool.self) { params in\n    switch params.name {\n    case \"search\":\n        let query = params.arguments?[\"query\"]?.stringValue ?? \"\"\n        let limit = params.arguments?[\"limit\"]?.intValue ?? 10\n        \n        // Perform search\n        let results = performSearch(query: query, limit: limit)\n        \n        return .init(\n            content: [.text(\"Found \\(results.count) results\")],\n            isError: false\n        )\n        \n    default:\n        return .init(\n            content: [.text(\"Unknown tool\")],\n            isError: true\n        )\n    }\n}\n```\n\n## Adding Resources\n\nImplement resource handlers for data access:\n\n```swift\n// Register resource list handler\nawait server.withMethodHandler(ListResources.self) { params in\n    let resources = [\n        Resource(\n            name: \"Data File\",\n            uri: \"resource://data/example.txt\",\n            description: \"Example data file\",\n            mimeType: \"text/plain\"\n        )\n    ]\n    return .init(resources: resources, nextCursor: nil)\n}\n\n// Register resource read handler\nawait server.withMethodHandler(ReadResource.self) { params in\n    switch params.uri {\n    case \"resource://data/example.txt\":\n        let content = loadResourceContent(uri: params.uri)\n        return .init(contents: [\n            Resource.Content.text(\n                content,\n                uri: params.uri,\n                mimeType: \"text/plain\"\n            )\n        ])\n        \n    default:\n        throw MCPError.invalidParams(\"Unknown resource URI: \\(params.uri)\")\n    }\n}\n\n// Register resource subscribe handler\nawait server.withMethodHandler(ResourceSubscribe.self) { params in\n    // Track subscription for notifications\n    subscriptions.insert(params.uri)\n    print(\"Client subscribed to \\(params.uri)\")\n    return .init()\n}\n```\n\n## Adding Prompts\n\nImplement prompt handlers for templated conversations:\n\n```swift\n// Register prompt list handler\nawait server.withMethodHandler(ListPrompts.self) { params in\n    let prompts = [\n        Prompt(\n            name: \"analyze\",\n            description: \"Analyze a topic\",\n            arguments: [\n                .init(name: \"topic\", description: \"Topic to analyze\", required: true),\n                .init(name: \"depth\", description: \"Analysis depth\", required: false)\n            ]\n        )\n    ]\n    return .init(prompts: prompts, nextCursor: nil)\n}\n\n// Register prompt get handler\nawait server.withMethodHandler(GetPrompt.self) { params in\n    switch params.name {\n    case \"analyze\":\n        let topic = params.arguments?[\"topic\"]?.stringValue ?? \"general\"\n        let depth = params.arguments?[\"depth\"]?.stringValue ?? \"basic\"\n        \n        let description = \"Analysis of \\(topic) at \\(depth) level\"\n        let messages: [Prompt.Message] = [\n            .user(\"Please analyze this topic: \\(topic)\"),\n            .assistant(\"I'll provide a \\(depth) analysis of \\(topic)\")\n        ]\n        \n        return .init(description: description, messages: messages)\n        \n    default:\n        throw MCPError.invalidParams(\"Unknown prompt: \\(params.name)\")\n    }\n}\n```\n\n## Transport Configuration\n\n### Stdio Transport\n\nFor local subprocess communication:\n\n```swift\nimport MCP\nimport Logging\n\nlet logger = Logger(label: \"com.example.mcp-server\")\nlet transport = StdioTransport(logger: logger)\n\ntry await server.start(transport: transport)\n```\n\n### HTTP Transport (Client Side)\n\nFor remote server connections:\n\n```swift\nlet transport = HTTPClientTransport(\n    endpoint: URL(string: \"http://localhost:8080\")!,\n    streaming: true  // Enable Server-Sent Events\n)\n\ntry await client.connect(transport: transport)\n```\n\n## Concurrency and Actors\n\nThe server is an actor, ensuring thread-safe access:\n\n```swift\nactor ServerState {\n    private var subscriptions: Set\u003cString\u003e = []\n    private var cache: [String: Any] = [:]\n    \n    func addSubscription(_ uri: String) {\n        subscriptions.insert(uri)\n    }\n    \n    func getSubscriptions() -\u003e Set\u003cString\u003e {\n        return subscriptions\n    }\n}\n\nlet state = ServerState()\n\nawait server.withMethodHandler(ResourceSubscribe.self) { params in\n    await state.addSubscription(params.uri)\n    return .init()\n}\n```\n\n## Error Handling\n\nUse Swift's error handling with `MCPError`:\n\n```swift\nawait server.withMethodHandler(CallTool.self) { params in\n    do {\n        guard let query = params.arguments?[\"query\"]?.stringValue else {\n            throw MCPError.invalidParams(\"Missing query parameter\")\n        }\n        \n        let result = try performOperation(query: query)\n        \n        return .init(\n            content: [.text(result)],\n            isError: false\n        )\n    } catch let error as MCPError {\n        return .init(\n            content: [.text(error.localizedDescription)],\n            isError: true\n        )\n    } catch {\n        return .init(\n            content: [.text(\"Unexpected error: \\(error.localizedDescription)\")],\n            isError: true\n        )\n    }\n}\n```\n\n## JSON Schema with Value Type\n\nUse the `Value` type for JSON schemas:\n\n```swift\nlet schema = Value.object([\n    \"type\": .string(\"object\"),\n    \"properties\": .object([\n        \"name\": .object([\n            \"type\": .string(\"string\"),\n            \"description\": .string(\"User's name\")\n        ]),\n        \"age\": .object([\n            \"type\": .string(\"integer\"),\n            \"minimum\": .number(0),\n            \"maximum\": .number(150)\n        ]),\n        \"email\": .object([\n            \"type\": .string(\"string\"),\n            \"format\": .string(\"email\")\n        ])\n    ]),\n    \"required\": .array([.string(\"name\")])\n])\n```\n\n## Swift Package Manager Setup\n\nCreate your `Package.swift`:\n\n```swift\n// swift-tools-version: 6.0\nimport PackageDescription\n\nlet package = Package(\n    name: \"MyMCPServer\",\n    platforms: [\n        .macOS(.v13),\n        .iOS(.v16)\n    ],\n    dependencies: [\n        .package(\n            url: \"https://github.com/modelcontextprotocol/swift-sdk.git\",\n            from: \"0.10.0\"\n        ),\n        .package(\n            url: \"https://github.com/apple/swift-log.git\",\n            from: \"1.5.0\"\n        )\n    ],\n    targets: [\n        .executableTarget(\n            name: \"MyMCPServer\",\n            dependencies: [\n                .product(name: \"MCP\", package: \"swift-sdk\"),\n                .product(name: \"Logging\", package: \"swift-log\")\n            ]\n        )\n    ]\n)\n```\n\n## Graceful Shutdown with ServiceLifecycle\n\nUse Swift Service Lifecycle for proper shutdown:\n\n```swift\nimport MCP\nimport ServiceLifecycle\nimport Logging\n\nstruct MCPService: Service {\n    let server: Server\n    let transport: Transport\n    \n    func run() async throws {\n        try await server.start(transport: transport)\n        try await Task.sleep(for: .days(365 * 100))\n    }\n    \n    func shutdown() async throws {\n        await server.stop()\n    }\n}\n\nlet logger = Logger(label: \"com.example.mcp-server\")\nlet transport = StdioTransport(logger: logger)\nlet mcpService = MCPService(server: server, transport: transport)\n\nlet serviceGroup = ServiceGroup(\n    services: [mcpService],\n    configuration: .init(\n        gracefulShutdownSignals: [.sigterm, .sigint]\n    ),\n    logger: logger\n)\n\ntry await serviceGroup.run()\n```\n\n## Async/Await Patterns\n\nAll server operations use Swift concurrency:\n\n```swift\nawait server.withMethodHandler(CallTool.self) { params in\n    async let result1 = fetchData1()\n    async let result2 = fetchData2()\n    \n    let combined = await \"\\(result1) and \\(result2)\"\n    \n    return .init(\n        content: [.text(combined)],\n        isError: false\n    )\n}\n```\n\n## Logging\n\nUse swift-log for structured logging:\n\n```swift\nimport Logging\n\nlet logger = Logger(label: \"com.example.mcp-server\")\n\nawait server.withMethodHandler(CallTool.self) { params in\n    logger.info(\"Tool called\", metadata: [\n        \"name\": .string(params.name),\n        \"args\": .string(\"\\(params.arguments ?? [:])\")\n    ])\n    \n    // Process tool call\n    \n    logger.debug(\"Tool completed successfully\")\n    \n    return .init(content: [.text(\"Result\")], isError: false)\n}\n```\n\n## Testing\n\nTest your server with async/await:\n\n```swift\nimport XCTest\n@testable import MyMCPServer\n\nfinal class ServerTests: XCTestCase {\n    func testToolCall() async throws {\n        let server = createTestServer()\n        \n        // Test tool call logic\n        let params = CallTool.Params(\n            name: \"search\",\n            arguments: [\"query\": .string(\"test\")]\n        )\n        \n        // Verify behavior\n        XCTAssertNoThrow(try await processToolCall(params))\n    }\n}\n```\n\n## Initialize Hook\n\nValidate client connections with an initialize hook:\n\n```swift\ntry await server.start(transport: transport) { clientInfo, clientCapabilities in\n    // Validate client\n    guard clientInfo.name != \"BlockedClient\" else {\n        throw MCPError.invalidRequest(\"Client not allowed\")\n    }\n    \n    // Check capabilities\n    if clientCapabilities.sampling == nil {\n        logger.warning(\"Client doesn't support sampling\")\n    }\n    \n    logger.info(\"Client connected\", metadata: [\n        \"name\": .string(clientInfo.name),\n        \"version\": .string(clientInfo.version)\n    ])\n}\n```\n\n## Common Patterns\n\n### Content Types\n\nHandle different content types:\n\n```swift\nreturn .init(\n    content: [\n        .text(\"Plain text response\"),\n        .image(imageData, mimeType: \"image/png\", metadata: [\n            \"width\": 1024,\n            \"height\": 768\n        ]),\n        .resource(\n            uri: \"resource://data\",\n            mimeType: \"application/json\",\n            text: jsonString\n        )\n    ],\n    isError: false\n)\n```\n\n### Strict Configuration\n\nUse strict mode to fail fast on missing capabilities:\n\n```swift\nlet client = Client(\n    name: \"StrictClient\",\n    version: \"1.0.0\",\n    configuration: .strict\n)\n\n// Will throw immediately if capability not available\ntry await client.listTools()\n```\n\n### Request Batching\n\nSend multiple requests efficiently:\n\n```swift\nvar tasks: [Task\u003cCallTool.Result, Error\u003e] = []\n\ntry await client.withBatch { batch in\n    for i in 0..\u003c10 {\n        tasks.append(\n            try await batch.addRequest(\n                CallTool.request(.init(\n                    name: \"process\",\n                    arguments: [\"id\": .number(Double(i))]\n                ))\n            )\n        )\n    }\n}\n\nfor (index, task) in tasks.enumerated() {\n    let result = try await task.value\n    print(\"\\(index): \\(result.content)\")\n}\n```\n","description":"Best practices and patterns for building Model Context Protocol (MCP) servers in Swift using the official MCP Swift SDK package.","import":{"commit_sha":"541b7819d8c3545c6df122491af4fa1eae415779","imported_at":"2026-05-18T20:05:35Z","license_text":"MIT License\n\nCopyright GitHub, Inc.\n\nPermission is hereby granted, free of charge, to any person obtaining a copy\nof this software and associated documentation files (the \"Software\"), to deal\nin the Software without restriction, including without limitation the rights\nto use, copy, modify, merge, publish, distribute, sublicense, and/or sell\ncopies of the Software, and to permit persons to whom the Software is\nfurnished to do so, subject to the following conditions:\n\nThe above copyright notice and this permission notice shall be included in all\ncopies or substantial portions of the Software.\n\nTHE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\nIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,\nFITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE\nAUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER\nLIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,\nOUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE\nSOFTWARE.","owner":"github","repo":"github/awesome-copilot","source_url":"https://github.com/github/awesome-copilot/blob/541b7819d8c3545c6df122491af4fa1eae415779/instructions/swift-mcp-server.instructions.md"},"manifest":{}},"content_hash":[120,136,3,51,12,184,197,210,91,63,230,222,63,119,254,14,171,236,137,131,183,20,47,32,44,34,232,41,155,111,9,238],"trust_level":"unsigned","yanked":false}