[DO-NOT-MERGE] feat: MCP Apps compose-email tool

README.md

@@ -126,6 +126,58 @@ pnpm run build
 }
 ```
 
+### Running on Localhost (HTTP Server)
+
+You can run the MCP server as an HTTP server on localhost for testing or integration with web applications.
+
+1. **Build the project** (if you haven't already):
+
+   ```bash
+   pnpm install
+   pnpm run build
+   ```
+
+2. **Set your API key**:
+
+   ```bash
+   export RESEND_API_KEY=re_your_key_here
+   ```
+
+3. **Start the HTTP server**:
+
+   ```bash
+   pnpm run dev
+   ```
+
+   Or with a custom port:
+
+   ```bash
+   node build/index.js --http --port 8080 --key=re_your_key_here
+   ```
+
+4. **Access the server**:
+
+   - **Health check**: http://localhost:3000/health
+   - **MCP endpoint**: http://localhost:3000/mcp
+
+The HTTP server supports:
+- **POST /mcp**: Send MCP requests (JSON-RPC)
+- **GET /mcp**: Server-Sent Events (SSE) streaming for long-running operations
+- **GET /sse**: SSE endpoint for ChatGPT compatibility
+- **GET /health**: Health check endpoint
+
+**ChatGPT Custom Apps:**
+- Use `http://localhost:3000/mcp` or `http://localhost:3000/sse` as the server URL
+- The server supports both MCP Apps and ChatGPT Apps SDK protocols
+- Interactive email composition UI is available via the `compose_email` tool
+
+**Command-line options for HTTP mode:**
+- `--http` or `--server`: Enable HTTP server mode
+- `--port` or `-p`: Set the port (default: 3000)
+- `--key`: Your Resend API key (or use `RESEND_API_KEY` environment variable)
+- `--sender`: Sender email address (optional)
+- `--reply-to`: Reply-to email address (optional)
+
 ### Testing with MCP Inspector
 
 > **Note:** Make sure you've built the project first (see [Setup](#setup) section above).

index.ts

@@ -4,9 +4,11 @@ import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js'
 import minimist from 'minimist';
 import { Resend } from 'resend';
 import packageJson from './package.json' with { type: 'json' };
+import { startHttpServer } from './server/http.js';
 import {
   addApiKeyTools,
   addBroadcastTools,
+  addComposeEmailTool,
   addContactPropertyTools,
   addContactTools,
   addDomainTools,
@@ -46,7 +48,6 @@ if (!apiKey) {
 
 const resend = new Resend(apiKey);
 
-// Create server instance
 const server = new McpServer({
   name: 'email-sending-service',
   version: packageJson.version,
@@ -61,14 +62,23 @@ addContactPropertyTools(server, resend);
 addContactTools(server, resend);
 addDomainTools(server, resend);
 addEmailTools(server, resend, { senderEmailAddress, replierEmailAddresses });
+addComposeEmailTool(server, resend, {
+  senderEmailAddress,
+  replierEmailAddresses,
+});
 addSegmentTools(server, resend);
 addTopicTools(server, resend);
 addWebhookTools(server, resend);
 
 async function main() {
-  const transport = new StdioServerTransport();
-  await server.connect(transport);
-  console.error('Email sending service MCP Server running on stdio');
+  if (argv.http || argv.server) {
+    const port = argv.port || argv.p || process.env.PORT || 3000;
+    await startHttpServer(server, port);
+  } else {
+    const transport = new StdioServerTransport();
+    await server.connect(transport);
+    console.error('Email sending service MCP Server running on stdio');
+  }
 }
 
 main().catch((error) => {

package.json

@@ -10,14 +10,18 @@
     "dist"
   ],
   "scripts": {
+    "dev": "node dist/index.js --http --port 3000",
+    "start": "node dist/index.js",
     "build": "tsc && node -e \"require('fs').chmodSync('dist/index.js', '755')\"",
     "prepare": "npm run build",
     "inspector": "npx @modelcontextprotocol/inspector@latest",
     "lint": "biome check .",
     "lint:fix": "biome check . --write"
   },
   "dependencies": {
+    "@mcp-ui/server": "^6.0.1",
     "@modelcontextprotocol/sdk": "1.25.2",
+    "express": "^5.2.1",
     "minimist": "1.2.8",
     "resend": "6.9.1",
     "zod": "4.3.6"
@@ -27,6 +31,7 @@
   },
   "devDependencies": {
     "@biomejs/biome": "2.3.10",
+    "@types/express": "^5.0.0",
     "@types/minimist": "1.2.5",
     "@types/node": "25.0.3",
     "typescript": "5.9.3"