Connect Web MCP

Web MCP lets a Model Context Protocol client — Claude Desktop, Cursor, an MCP-aware browser extension, or any other MCP host — act on your not24get account directly from the browser tab where you are signed in. The host can search and create bookmarks, list and create folders, and read workspace metadata, all under your existing session.

Requirements

• A signed-in not24get session in a Chromium-based browser (Chrome, Edge, Brave, Arc).
• A secure context — https://not24get.me or http://localhost for local development.
• One of the following MCP transports:
  • Browser Extension — an MCP-aware browser extension that exposes navigator.modelContext (for example, MCP-B), or Chrome 146+ with the native flag at chrome://flags/#enable-webmcp-testing enabled.
  • Local Agent — the not24get Local Agent relay running on 127.0.0.1:9333. Use this when you cannot install a browser extension or when you want a desktop MCP host (Claude Desktop, Cursor) to drive the page.

Setup

1. ●

   Open the Web MCP panel

   From the bookmark hub, open the Web MCP panel. It shows the current connection state and which transport is active.

2. ●

   Pick a transport

   Click Connect to Browser Extension if you have an MCP-aware extension installed (or have enabled the native WebMCP flag). Click Connect to Local Agent if you are running the Local Agent relay on 127.0.0.1:9333.

3. ●

   Confirm the connection

   The panel changes to Connected via Browser Extension or Connected via Local Agent and lists the registered tools. Your MCP client (extension sidebar or desktop host) now shows the not24get tools and can call them.

4. ●

   Disconnect when you are done

   Click Disconnect in the panel to unregister the tools and close the relay socket.

Using a desktop MCP host with the Local Agent

When you connect a desktop client like Claude Desktop or Cursor, the not24get tab does the actual work — the desktop host sends tool calls over the relay to the tab.

1. ●

   Start the Local Agent

   Run the not24get Local Agent on your machine. It listens on ws://127.0.0.1:9333 by default.

   The reference relay is published as @mcp-b/webmcp-local-relay on npm. Most MCP hosts can launch it for you — declare it as an MCP server in the host's config and the host will spawn the relay on demand.

2. ●

   Add the relay to your MCP host config

   Most MCP hosts (Claude Desktop, Cursor, etc.) accept a JSON mcpServers block. Add an entry that runs the relay via npx:

   Copy

   {
     "mcpServers": {
       "webmcp-local-relay": {
         "command": "npx",
         "args": ["-y", "@mcp-b/webmcp-local-relay@latest"]
       }
     }
   }
   

   The exact location varies by host — Claude Desktop reads claude_desktop_config.json, Cursor reads ~/.cursor/mcp.json. Save the file and restart the host so it picks up the new server.

3. ●

   Open not24get in a tab and click Connect to Local Agent

   The tab handshakes with the relay on ws://127.0.0.1:9333 and registers the tools listed in Available tools. The Web MCP panel in the tab confirms Connected via Local Agent.

4. ●

   Verify the host can see the tools

   In your MCP host, the webmcp-local-relay server should now list every not24get tool (search bookmarks, list workspaces, etc.). Invoking one runs against the open tab in real time.

Troubleshooting

• "No usable navigator.modelContext" — your browser does not expose Web MCP. Install an MCP-aware extension, or use the Local Agent transport.
• "WebMCP relay did not respond within 5000ms" — the Local Agent is not running, or it is running on a different port. Start the agent and retry. In the Web MCP panel you can change the Local Agent relay port (default 9333); the choice is saved in your browser. Deployments can also set WEB_MCP_RELAY_PORT (or VITE_WEB_MCP_RELAY_PORT in dev builds).
• Tools missing from the host — refresh the not24get tab and reconnect. The tool list is published when the page connects.

For step-by-step diagnosis (port split between 9333 and 9334, list_sources returning zero, 25-second tool timeouts, and multiple-tab tool suffixes), see the WebMCP operator skill.

What's next

• Available tools — the full list of tools, resources, and prompts that Web MCP exposes.
• WebMCP operator skill — configure Local Agent and Cursor, verify health checks, and fix common relay problems.