Update MCP TypeScript SDK to v2

Adopt the split v2 packages and factory-based stdio serving so the server supports modern protocol clients while retaining legacy compatibility.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: yamanoku

baseline-mcp-server.test.ts

@@ -0,0 +1,56 @@
+import { Client, InMemoryTransport } from "@modelcontextprotocol/client";
+import { assertEquals } from "@std/assert";
+import { createMCPServer } from "./baseline-mcp-server.ts";
+
+Deno.test("MCPサーバーがツールと入力スキーマを公開する", async () => {
+  const server = createMCPServer();
+  const client = new Client({
+    name: "baseline-mcp-server-test",
+    version: "1.0.0",
+  });
+  const [clientTransport, serverTransport] = InMemoryTransport
+    .createLinkedPair();
+
+  await server.connect(serverTransport);
+  await client.connect(clientTransport);
+
+  try {
+    const { tools } = await client.listTools();
+
+    assertEquals(
+      tools.map(({ name }) => name),
+      [
+        "get_web_feature_baseline_status",
+        "get_negated_browser_baseline_status",
+      ],
+    );
+    assertEquals(tools[0].inputSchema, {
+      $schema: "https://json-schema.org/draft/2020-12/schema",
+      type: "object",
+      properties: {
+        query: {
+          description: "調べたい機能の名前",
+          type: "array",
+          items: { type: "string" },
+        },
+      },
+      required: ["query"],
+    });
+    assertEquals(tools[1].inputSchema, {
+      $schema: "https://json-schema.org/draft/2020-12/schema",
+      type: "object",
+      properties: {
+        query: {
+          description:
+            "除外したいブラウザの名前（chrome, edge, firefox, safari）",
+          type: "string",
+          enum: ["chrome", "edge", "firefox", "safari"],
+        },
+      },
+      required: ["query"],
+    });
+  } finally {
+    await client.close();
+    await server.close();
+  }
+});

baseline-mcp-server.ts

@@ -1,57 +1,56 @@
 // baseline-mcp-server.ts
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
+import { McpServer } from "@modelcontextprotocol/server";
+import { serveStdio } from "@modelcontextprotocol/server/stdio";
 import { z } from "zod";
 import {
   getNegatedBrowserBaselineStatusAsMCPContent,
   getWebFeatureBaselineStatusAsMCPContent,
 } from "./tools/index.ts";
-import { BROWSERS, type Browsers } from "./types.ts";
+import { BROWSERS } from "./types.ts";
 import DenoJSON from "./deno.json" with { type: "json" };
 
-// MCPサーバーの初期化
-const server = new McpServer({
-  name: "Baseline MCP Server",
-  version: DenoJSON.version,
-  capabilities: {
-    tools: {},
-  },
-});
+export function createMCPServer(): McpServer {
+  const server = new McpServer({
+    name: "Baseline MCP Server",
+    version: DenoJSON.version,
+  });
 
-// 特定の機能のBaselineステータスを取得
-server.tool(
-  "get_web_feature_baseline_status",
-  "クエリを指定し、Web Platform Dashboardからfeatureの結果を取得します",
-  {
-    query: z.string().array().describe("調べたい機能の名前"),
-  },
-  async ({ query }: { query: string | string[] }) => {
-    return await getWebFeatureBaselineStatusAsMCPContent(query);
-  },
-);
+  // 特定の機能のBaselineステータスを取得
+  server.registerTool(
+    "get_web_feature_baseline_status",
+    {
+      description:
+        "クエリを指定し、Web Platform Dashboardからfeatureの結果を取得します",
+      inputSchema: z.object({
+        query: z.array(z.string()).describe("調べたい機能の名前"),
+      }),
+    },
+    async ({ query }) => {
+      return await getWebFeatureBaselineStatusAsMCPContent(query);
+    },
+  );
 
-// 特定のブラウザを除外した機能を検索
-server.tool(
-  "get_negated_browser_baseline_status",
-  "特定のブラウザを除外して、Web Platform Dashboardからfeatureの結果を取得します",
-  {
-    query: z.enum(BROWSERS).describe(
-      "除外したいブラウザの名前（chrome, edge, firefox, safari）",
-    ),
-  },
-  async ({ query }: { query: Browsers }) => {
-    return await getNegatedBrowserBaselineStatusAsMCPContent(query);
-  },
-);
+  // 特定のブラウザを除外した機能を検索
+  server.registerTool(
+    "get_negated_browser_baseline_status",
+    {
+      description:
+        "特定のブラウザを除外して、Web Platform Dashboardからfeatureの結果を取得します",
+      inputSchema: z.object({
+        query: z.enum(BROWSERS).describe(
+          "除外したいブラウザの名前（chrome, edge, firefox, safari）",
+        ),
+      }),
+    },
+    async ({ query }) => {
+      return await getNegatedBrowserBaselineStatusAsMCPContent(query);
+    },
+  );
 
-// 起動
-async function setMCPServer() {
-  const transport = new StdioServerTransport();
-  await server.connect(transport);
-  console.error("Baseline MCP Server running on stdio");
+  return server;
 }
 
-setMCPServer().catch((error) => {
-  console.error("Fatal error in setMCPServer():", error);
-  Deno.exit(1);
-});
+if (import.meta.main) {
+  serveStdio(createMCPServer);
+  console.error("Baseline MCP Server running on stdio");
+}

deno.json

@@ -13,9 +13,9 @@
     "fmt": "deno fmt"
   },
   "imports": {
-    "@modelcontextprotocol/sdk": "npm:@modelcontextprotocol/sdk@^1.30.0",
-    "@modelcontextprotocol/sdk/server/mcp.js": "npm:@modelcontextprotocol/sdk@^1.30.0/server/mcp.js",
-    "@modelcontextprotocol/sdk/server/stdio.js": "npm:@modelcontextprotocol/sdk@^1.30.0/server/stdio.js",
+    "@modelcontextprotocol/client": "npm:@modelcontextprotocol/client@^2.0.0",
+    "@modelcontextprotocol/server": "npm:@modelcontextprotocol/server@^2.0.0",
+    "@modelcontextprotocol/server/stdio": "npm:@modelcontextprotocol/server@^2.0.0/stdio",
     "@std/assert": "jsr:@std/assert@^1.0.19",
     "zod": "npm:zod@^4.4.3"
   },