fix: Move streamable HTTP transport from /mcp to root / (#529)

* Initial plan

* Move streamable transport from /mcp to root /

Co-authored-by: jirispilka <19406805+jirispilka@users.noreply.github.com>

* Update src/actor/server.ts

* Remove GET / handler and update DEVELOPMENT.md endpoint references

Co-authored-by: jirispilka <19406805+jirispilka@users.noreply.github.com>

* Revert MCP_STREAMABLE_ENDPOINT change in src/const.ts

Co-authored-by: jirispilka <19406805+jirispilka@users.noreply.github.com>

* refactor: Update MCP route to return 405 for unsupported GET requests

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: jirispilka <19406805+jirispilka@users.noreply.github.com>
Co-authored-by: Jiří Spilka <jiri.spilka@apify.com>
Co-authored-by: Jiri Spilka <jirka.spilka@gmail.com>

Author: Copilot

DEVELOPMENT.md

@@ -66,7 +66,7 @@ This command builds the core project and the `src/web/` widgets, then copies the
 
 All widget code lives in the self-contained `src/web/` React project. The widgets (MCP Apps) are rendered based on the structured output returned by MCP tools. If you need to add specific data to a widget, modify the corresponding MCP tool's output, since widgets can only render data returned by the MCP tool call result.
 
-> **Important (UI mode):** Widget rendering is enabled only when the server runs in UI mode. Use the `ui=openai` query parameter (e.g., `/mcp?ui=openai`) or set `UI_MODE=openai`. Currently, `openai` is the only supported `ui` value.
+> **Important (UI mode):** Widget rendering is enabled only when the server runs in UI mode. Use the `ui=openai` query parameter (e.g., `/?ui=openai`) or set `UI_MODE=openai`. Currently, `openai` is the only supported `ui` value.
 
 ### Hot-reload development
 
@@ -150,7 +150,7 @@ You can use [MCPJam](https://www.mcpjam.com/) to connect to and test the MCP ser
 
 1. Click **"Add new server"**
 2. Fill in a name for the server
-3. Enter the URL: `http://localhost:3001/mcp?ui=openai` (Note: the `ui=openai` query parameter is required for widget rendering)
+3. Enter the URL: `http://localhost:3001/?ui=openai` (Note: the `ui=openai` query parameter is required for widget rendering)
 4. Select **"No authentication"** as the auth method
 5. Click **Add**
 
@@ -196,13 +196,13 @@ Then start the tunnel:
 ngrok start app
 ```
 
-The MCP server API will be reachable at `https://mcp-apify.ngrok.dev/mcp?ui=openai`.
+The MCP server API will be reachable at `https://mcp-apify.ngrok.dev/?ui=openai`.
 
 #### Adding the server in ChatGPT
 
 1. Go to [chatgpt.com](https://chatgpt.com) and open **Settings → Connectors**
 2. Click **"Add a custom connector"**
-3. Enter the URL: `https://mcp-apify.ngrok.dev/mcp?ui=openai`
+3. Enter the URL: `https://mcp-apify.ngrok.dev/?ui=openai`
 4. Save and start a new chat
 
 > **Important:** After restarting ngrok, use the **Refresh** button in the connector settings to reconnect — ChatGPT does not detect the tunnel restart automatically.

package-lock.json

@@ -9,8 +9,7 @@ export enum TransportType {
 }
 
 export enum Routes {
-    ROOT = '/',
-    MCP = '/mcp',
+    MCP = '/',
     SSE = '/sse',
     MESSAGE = '/message',
 }

src/actor/const.ts

@@ -18,8 +18,7 @@ import { ApifyClient } from '../apify_client.js';
 import { ActorsMcpServer } from '../mcp/server.js';
 import type { ApifyRequestParams } from '../types.js';
 import { parseUiMode } from '../types.js';
-import { getHelpMessage, HEADER_READINESS_PROBE, Routes, TransportType } from './const.js';
-import { getActorRunData } from './utils.js';
+import { getHelpMessage, Routes, TransportType } from './const.js';
 
 export function createExpressApp(
     host: string,
@@ -51,31 +50,6 @@ export function createExpressApp(
         }
     }
 
-    app.get(Routes.ROOT, async (req: Request, res: Response) => {
-        if (req.headers && req.get(HEADER_READINESS_PROBE) !== undefined) {
-            log.debug('Received readiness probe');
-            res.status(200).json({ message: 'Server is ready' }).end();
-            return;
-        }
-        try {
-            log.info('MCP API', {
-                mth: req.method,
-                rt: Routes.ROOT,
-                tr: TransportType.HTTP,
-            });
-            res.setHeader('Content-Type', 'text/event-stream');
-            res.setHeader('Cache-Control', 'no-cache');
-            res.setHeader('Connection', 'keep-alive');
-            res.status(200).json({ message: `Actor is using Model Context Protocol. ${getHelpMessage(host)}`, data: getActorRunData() }).end();
-        } catch (error) {
-            respondWithError(res, error, `Error in GET ${Routes.ROOT}`);
-        }
-    });
-
-    app.head(Routes.ROOT, (_req: Request, res: Response) => {
-        res.status(200).end();
-    });
-
     app.get(Routes.SSE, async (req: Request, res: Response) => {
         try {
             log.info('MCP API', {
@@ -192,7 +166,7 @@ export function createExpressApp(
     });
 
     // express.json() middleware to parse JSON bodies.
-    // It must be used before the POST /mcp route but after the GET /sse route :shrug:
+    // It must be used before the POST / route but after the GET /sse route :shrug:
     app.use(express.json());
     app.post(Routes.MCP, async (req: Request, res: Response) => {
         log.info('Received MCP request:', req.body);