Switch MCP transport from stdio to Streamable HTTP

Mount POST /mcp on the main Express app (stateless Streamable HTTP).
Keep optional MCP-only HTTP process via npm run mcp. Update docs.

src/index.js

@@ -3,11 +3,14 @@ const { WebshareClient } = require('./webshare');
 const { caps, feed } = require('./torznab');
 const { makeTorrent } = require('./torrent');
 const qbt = require('./qbt');
+const { registerMcpHttp } = require('./mcp-http');
 
 const PORT = process.env.PORT || 3001;
 const BASE_URL = process.env.BASE_URL || `http://localhost:${PORT}`;
 const USERNAME = process.env.WEBSHARE_USERNAME;
 const PASSWORD = process.env.WEBSHARE_PASSWORD;
+const MCP_PATH = process.env.MCP_PATH || '/mcp';
+const MCP_ENABLED = process.env.MCP_ENABLED !== '0' && process.env.MCP_ENABLED !== 'false';
 
 if (!USERNAME || !PASSWORD) {
     console.error('WEBSHARE_USERNAME and WEBSHARE_PASSWORD must be set');
@@ -18,7 +21,7 @@ const client = new WebshareClient(USERNAME, PASSWORD);
 const app = express();
 
 app.use(express.urlencoded({ extended: false }));
-app.use(express.json());
+app.use(express.json({ limit: '4mb' }));
 
 client.ensureAuth().catch(err => console.error('Initial auth failed:', err.message));
 
@@ -113,6 +116,15 @@ app.get('/resolve/:ident', async (req, res) => {
 // ── Fake qBittorrent Web API ──────────────────────────────────────────────
 qbt.register(app);
 
+// ── MCP Streamable HTTP (AI agents) ───────────────────────────────────────
+if (MCP_ENABLED) {
+    registerMcpHttp(app, {
+        username: USERNAME,
+        password: PASSWORD,
+        path: MCP_PATH,
+    });
+}
+
 // ── Automatic missing-episode search ─────────────────────────────────────
 // Sonarr won't find new downloads without being asked (no RSS support).
 // Every 2 hours, tell Sonarr to search for all missing monitored episodes.
@@ -148,4 +160,9 @@ if (SONARR_KEY) {
     console.log(`[search] auto missing-episode search every ${SEARCH_INTERVAL / 3600000}h`);
 }
 
-app.listen(PORT, () => console.log(`webshare-api listening on :${PORT} — base URL: ${BASE_URL}`));
+app.listen(PORT, () => {
+    console.log(`webshare-api listening on :${PORT} — base URL: ${BASE_URL}`);
+    if (MCP_ENABLED) {
+        console.log(`MCP Streamable HTTP: POST ${BASE_URL.replace(/\/$/, '')}${MCP_PATH}`);
+    }
+});

src/mcp-http.js

@@ -0,0 +1,57 @@
+const { StreamableHTTPServerTransport } = require('@modelcontextprotocol/sdk/server/streamableHttp.js');
+const { createWebshareMcpServer } = require('./mcp-server');
+
+/**
+ * Mount a stateless Streamable HTTP MCP endpoint on an Express app.
+ * Default path: POST /mcp (MCP Streamable HTTP transport).
+ *
+ * @param {import('express').Express} app
+ * @param {{ username: string, password: string, path?: string }} options
+ */
+function registerMcpHttp(app, { username, password, path: mountPath = '/mcp' }) {
+    const handle = async (req, res) => {
+        // Stateless: one MCP server + transport per request
+        const server = createWebshareMcpServer({ username, password });
+        try {
+            const transport = new StreamableHTTPServerTransport({
+                sessionIdGenerator: undefined,
+            });
+            await server.connect(transport);
+            await transport.handleRequest(req, res, req.body);
+            res.on('close', () => {
+                try {
+                    transport.close();
+                } catch { /* ignore */ }
+                try {
+                    server.close();
+                } catch { /* ignore */ }
+            });
+        } catch (err) {
+            console.error('MCP HTTP error:', err);
+            if (!res.headersSent) {
+                res.status(500).json({
+                    jsonrpc: '2.0',
+                    error: { code: -32603, message: 'Internal server error' },
+                    id: null,
+                });
+            }
+        }
+    };
+
+    app.post(mountPath, handle);
+
+    // Streamable HTTP clients may probe GET/DELETE; this deployment is POST-only (stateless).
+    const methodNotAllowed = (req, res) => {
+        res.status(405).json({
+            jsonrpc: '2.0',
+            error: { code: -32000, message: 'Method not allowed. Use POST for Streamable HTTP (stateless).' },
+            id: null,
+        });
+    };
+    app.get(mountPath, methodNotAllowed);
+    app.delete(mountPath, methodNotAllowed);
+
+    console.log(`MCP Streamable HTTP enabled at POST ${mountPath}`);
+}
+
+module.exports = { registerMcpHttp };

src/mcp.js

@@ -1,32 +1,39 @@
 #!/usr/bin/env node
 /**
- * MCP stdio entrypoint for AI agents.
+ * Optional standalone HTTP process that only serves MCP (no Torznab / qBittorrent).
+ * Prefer `npm start` (main app) which mounts MCP at POST /mcp on the same port.
  *
- * Configure clients with:
- *   command: node
- *   args: ["…/webshare-api/src/mcp.js"]
- *   env: { WEBSHARE_USERNAME, WEBSHARE_PASSWORD }
- *
- * Do not write application logs to stdout — it is reserved for the MCP protocol.
+ * Env:
+ *   WEBSHARE_USERNAME, WEBSHARE_PASSWORD (required)
+ *   PORT (default 3001)
+ *   MCP_PATH (default /mcp)
  */
-const { StdioServerTransport } = require('@modelcontextprotocol/sdk/server/stdio.js');
-const { createWebshareMcpServer } = require('./mcp-server');
+const express = require('express');
+const { registerMcpHttp } = require('./mcp-http');
 
-async function main() {
-    const username = process.env.WEBSHARE_USERNAME;
-    const password = process.env.WEBSHARE_PASSWORD;
-    if (!username || !password) {
-        console.error('WEBSHARE_USERNAME and WEBSHARE_PASSWORD must be set');
-        process.exit(1);
-    }
+const PORT = process.env.PORT || 3001;
+const MCP_PATH = process.env.MCP_PATH || '/mcp';
+const USERNAME = process.env.WEBSHARE_USERNAME;
+const PASSWORD = process.env.WEBSHARE_PASSWORD;
 
-    const server = createWebshareMcpServer({ username, password });
-    const transport = new StdioServerTransport();
-    await server.connect(transport);
-    console.error('webshare-api MCP server running on stdio');
+if (!USERNAME || !PASSWORD) {
+    console.error('WEBSHARE_USERNAME and WEBSHARE_PASSWORD must be set');
+    process.exit(1);
 }
 
-main().catch((err) => {
-    console.error('MCP server failed:', err);
-    process.exit(1);
+const app = express();
+app.use(express.json({ limit: '4mb' }));
+
+app.get('/health', (req, res) => {
+    res.json({ ok: true, mcp: MCP_PATH });
+});
+
+registerMcpHttp(app, {
+    username: USERNAME,
+    password: PASSWORD,
+    path: MCP_PATH,
+});
+
+app.listen(PORT, () => {
+    console.log(`webshare-api MCP (HTTP) listening on :${PORT}${MCP_PATH}`);
 });