MCP Remote Mode vs. Local Mode

What is the difference between configuring an MCP server with a url versus a command/package?

{
  "mcpServers": {
    "guan": {
      "url": "https://guan-open.alibaba-inc.com/session/4347ef0c79ab595e9284f79cf3777558/sse"
    },
    "Figma": {
      "url": "https://mcp.figma.com/mcp"
    },
    "weavefox": {
      "command": "weavefox",
      "args": [
        "server"
      ],
      "disabled": false,
      "autoApprove": []
    },
    "ftraffic-code": {
      "url": "https://mcp.alibaba-inc.com/ftraffic-code/mcp",
      "headers": {}
    },
    "browsermcp": {
      "command": "npx",
      "args": [
        "@browsermcp/mcp@latest"
      ]
    }
  }
}

In short: url is Remote Mode (SSE), and command is Local Mode (Stdio).

Here is a detailed breakdown of the differences:

1. url Mode (SSE Transport) 🔗︎

This configuration is used to connect to a Web Server that is already running.

• How it works: The client (such as Claude Desktop or a browser plugin) acts as an HTTP client and connects to the specified URL using the SSE (Server-Sent Events) protocol.
• Examples like guan or Figma:
  • These are HTTP services already deployed in the cloud or on a corporate internal network.
  • The server-side code is already running on a remote host.
• Pros:
  • No local environment needed: Your computer does not need Node.js, Python, or any specific dependency packages installed.
  • Cross-platform: It works on Windows, Mac, or even within a browser, as long as there is internet connectivity.
  • Centralized management: A company can maintain a single server, and all employees can simply configure the same URL to use it.
• Cons: It cannot directly access your local file system (unless the server happens to be running on your localhost).

2. command / args Mode (Stdio Transport) 🔗︎

This configuration is used to launch a Local Process.

• How it works: The client spawns a subprocess directly on your machine and exchanges data via standard input/output (stdio/stdin/stdout).
• Examples like browsermcp or weavefox:
  • command: "npx" means the client will automatically execute npx @browsermcp/mcp@latest.
  • This downloads (if necessary) and starts the tool locally on your machine.
• Pros:
  • Local Permissions: The process inherits your local privileges, allowing it to read/write files, control your local browser, or access local databases.
  • On-demand Startup: The process is only started when you open the AI client and is automatically terminated when the client is closed.
• Cons:
  • Environment Dependencies: Your computer must have the required runtime installed (e.g., Node.js or Python).
  • Resource Consumption: Each server runs as an independent local process, consuming local CPU and memory.

3. Key Differences Comparison Table 🔗︎