feat: added @hono/mcp package

examples/mcp/hono-mcp/netlify/functions/hono-mcp-server.ts

@@ -1,82 +1,38 @@
 import { Hono } from "hono";
 import { handle } from 'hono/netlify'
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
-import { toFetchResponse, toReqRes } from "fetch-to-node";
+import { StreamableHTTPTransport } from "@hono/mcp"
 import { setupMCPServer } from "../mcp-server";
+import { HTTPException } from "hono/http-exception"
 
 const app = new Hono();
 
-app.post("/mcp", async (c) => {
-  // Convert the Request object into a Node.js Request object
-  const { req, res } = toReqRes(c.req.raw);
-
+app.all("/mcp", async (c) => {
   const server = setupMCPServer();
 
-  try {
-    const transport: StreamableHTTPServerTransport =
-      new StreamableHTTPServerTransport({
-        sessionIdGenerator: undefined,
-      });
-
-    await server.connect(transport);
-
-    await transport.handleRequest(req, res, await c.req.json());
+  const transport = new StreamableHTTPTransport();
+  await server.connect(transport);
+  return transport.handleRequest(c);
+});
 
-    res.on("close", () => {
-      console.log("Request closed");
-      transport.close();
-      server.close();
-    });
+app.onError((err, c) => {
+  console.log(err.message)
 
-    return toFetchResponse(res);
-  } catch (e) {
-    console.error(e);
-    return c.json(
-      {
-        jsonrpc: "2.0",
-        error: {
-          code: -32603,
-          message: "Internal server error",
-        },
-        id: null,
-      },
-      { status: 500 }
-    );
+  if (err instanceof HTTPException && err.res) {
+    return err.res
   }
-});
 
-app.get("/mcp", async (c) => {
-  // For the stateless server, GET requests are used to initialize
-  // SSE connections which are stateful. Therefore, we don't need
-  // to handle GET requests but we can signal to the client this error.
-  console.log("Received GET MCP request");
   return c.json(
     {
-      jsonrpc: "2.0",
+      jsonrpc: '2.0',
       error: {
-        code: -32000,
-        message: "Method not allowed.",
+        code: -32603,
+        message: 'Internal server error',
       },
       id: null,
     },
-    { status: 405 }
-  );
-});
-
-app.delete("/mcp", async (c) => {
-  console.log("Received DELETE MCP request");
-  return c.json(
-    {
-      jsonrpc: "2.0",
-      error: {
-        code: -32000,
-        message: "Method not allowed.",
-      },
-      id: null,
-    },
-    { status: 405 }
-  );
-});
+    500
+  )
+})
 
 export default handle(app);
 

examples/mcp/hono-mcp/package.json

@@ -6,9 +6,9 @@
     "type": "module",
     "license": "ISC",
     "dependencies": {
+        "@hono/mcp": "^0.1.0",
         "@modelcontextprotocol/sdk": "^1.10.2",
-        "fetch-to-node": "^2.0.0",
         "hono": "^4.7.7",
         "zod": "^3.24.3"
     }
-}
+}