Add streamable HTTP transport support

Co-authored-by: f <[email protected]>

Author: Copilot

cmd/mcptools/commands/new.go

@@ -15,6 +15,7 @@ const (
 	sdkTypeScript  = "ts"
 	transportStdio = "stdio"
 	transportSSE   = "sse"
+	transportHTTP  = "http"
 )
 
 // NewCmd returns a new 'new' command for scaffolding MCP projects.
@@ -30,7 +31,7 @@ func NewCmd() *cobra.Command {
 Examples:
   mcp new tool:hello_world resource:file prompt:hello
   mcp new tool:hello_world --sdk=ts
-  mcp new tool:hello_world --transport=stdio|sse`,
+  mcp new tool:hello_world --transport=stdio|sse|http`,
 		SilenceUsage: true,
 		RunE: func(_ *cobra.Command, args []string) error {
 			if len(args) == 0 {
@@ -48,8 +49,8 @@ Examples:
 			}
 
 			// Validate transport flag
-			if transportFlag != "" && transportFlag != transportStdio && transportFlag != transportSSE {
-				return fmt.Errorf("unsupported transport: %s (supported options: stdio, sse)", transportFlag)
+			if transportFlag != "" && transportFlag != transportStdio && transportFlag != transportSSE && transportFlag != transportHTTP {
+				return fmt.Errorf("unsupported transport: %s (supported options: stdio, sse, http)", transportFlag)
 			}
 
 			// Set default transport if not specified
@@ -84,7 +85,7 @@ Examples:
 
 	// Add flags
 	cmd.Flags().StringVar(&sdkFlag, "sdk", "", "Specify the SDK to use (ts)")
-	cmd.Flags().StringVar(&transportFlag, "transport", "", "Specify the transport to use (stdio, sse)")
+	cmd.Flags().StringVar(&transportFlag, "transport", "", "Specify the transport to use (stdio, sse, http)")
 
 	return cmd
 }
@@ -128,6 +129,8 @@ func createProjectStructure(components map[string]string, sdk, transport string)
 	var serverTemplateFile string
 	if transport == transportSSE {
 		serverTemplateFile = filepath.Join(templatesDir, "server_sse.ts")
+	} else if transport == transportHTTP {
+		serverTemplateFile = filepath.Join(templatesDir, "server_http.ts")
 	} else {
 		// Use stdio by default
 		serverTemplateFile = filepath.Join(templatesDir, "server_stdio.ts")

cmd/mcptools/commands/root.go

@@ -16,6 +16,7 @@ const (
 	FlagHelp        = "--help"
 	FlagHelpShort   = "-h"
 	FlagServerLogs  = "--server-logs"
+	FlagTransport   = "--transport"
 )
 
 // entity types.
@@ -34,6 +35,9 @@ var (
 	ParamsString string
 	// ShowServerLogs is a flag to show server logs.
 	ShowServerLogs bool
+	// TransportOption is the transport option for HTTP connections, valid values are "sse" and "http".
+	// Default is "http" (streamable HTTP).
+	TransportOption = "http"
 )
 
 // RootCmd creates the root command.
@@ -48,6 +52,7 @@ It allows you to discover and call tools, list resources, and interact with MCP-
 	cmd.PersistentFlags().StringVarP(&FormatOption, "format", "f", "table", "Output format (table, json, pretty)")
 	cmd.PersistentFlags().
 		StringVarP(&ParamsString, "params", "p", "{}", "JSON string of parameters to pass to the tool (for call command)")
+	cmd.PersistentFlags().StringVar(&TransportOption, "transport", "http", "HTTP transport type (http, sse)")
 
 	return cmd
 }

cmd/mcptools/commands/utils.go

@@ -47,7 +47,17 @@ var CreateClientFunc = func(args []string, _ ...client.ClientOption) (*client.Cl
 	var err error
 
 	if len(args) == 1 && IsHTTP(args[0]) {
-		c, err = client.NewSSEMCPClient(args[0])
+		// Validate transport option for HTTP URLs
+		if TransportOption != "http" && TransportOption != "sse" {
+			return nil, fmt.Errorf("invalid transport option: %s (supported: http, sse)", TransportOption)
+		}
+		
+		if TransportOption == "sse" {
+			c, err = client.NewSSEMCPClient(args[0])
+		} else {
+			// Default to streamable HTTP
+			c, err = client.NewStreamableHttpClient(args[0])
+		}
 		if err != nil {
 			return nil, err
 		}
@@ -91,6 +101,7 @@ var CreateClientFunc = func(args []string, _ ...client.ClientOption) (*client.Cl
 
 // ProcessFlags processes command line flags, sets the format option, and returns the remaining
 // arguments. Supported format options: json, pretty, and table.
+// Supported transport options: http and sse.
 //
 // For example, if the input arguments are ["tools", "--format", "pretty", "npx", "-y",
 // "@modelcontextprotocol/server-filesystem", "~"], it would return ["npx", "-y",
@@ -104,6 +115,9 @@ func ProcessFlags(args []string) []string {
 		case (args[i] == FlagFormat || args[i] == FlagFormatShort) && i+1 < len(args):
 			FormatOption = args[i+1]
 			i += 2
+		case args[i] == FlagTransport && i+1 < len(args):
+			TransportOption = args[i+1]
+			i += 2
 		case args[i] == FlagServerLogs:
 			ShowServerLogs = true
 			i++

templates/ts/server_http.ts

@@ -0,0 +1,42 @@
+import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import express from "express";
+import { z } from "zod";
+import { randomUUID } from "crypto";
+
+// Initialize server
+const server = new McpServer({
+  name: "PROJECT_NAME",
+  version: "1.0.0"
+});
+
+// Initialize components here
+// COMPONENT_INITIALIZATION
+
+// Setup Express app
+const app = express();
+
+// Enable JSON parsing for request bodies
+app.use(express.json());
+
+// Create a streamable HTTP transport
+const transport = new StreamableHTTPServerTransport({
+  // Enable session management with auto-generated UUIDs
+  sessionIdGenerator: () => randomUUID(),
+  // Optional: Enable JSON response mode for simple request/response
+  enableJsonResponse: false
+});
+
+// Handle all HTTP methods on the root path
+app.all("/", async (req, res) => {
+  await transport.handleRequest(req, res, req.body);
+});
+
+// Connect the server to the transport
+await server.connect(transport);
+
+// Start HTTP server
+const port = 3000;
+app.listen(port, () => {
+  console.log(`MCP server running on http://localhost:${port}`);
+});