Skip to main content

​
Connection Types for MCP Servers

MCP servers can communicate with clients using different connection protocols, each with its own advantages and use cases. This guide explains the primary connection types supported by mcp_use:

​
Standard Input/Output (STDIO)

STDIO connections run the MCP server as a child process and communicate through standard input and output streams.

​
Characteristics:

  • Local Operation: The server runs as a child process on the same machine
  • Simplicity: Easy to set up with minimal configuration
  • Security: No network exposure, ideal for sensitive operations
  • Performance: Low latency for local operations

​
Configuration Example:

{
  "mcpServers": {
    "stdio_server": {
      "command": "npx",
      "args": ["@my-mcp/server"],
      "env": {}
    }
  }
}

​
HTTP Connections

HTTP connections communicate with MCP servers over standard HTTP/HTTPS protocols.

​
Configuration Example:

{
  "mcpServers": {
    "http_server": {
      "url": "http://localhost:3000",
      "headers": {
        "Authorization": "Bearer ${AUTH_TOKEN}"
      }
    }
  }
}

​
Choosing the Right Connection Type

The choice of connection type depends on your specific use case:
  1. STDIO: Best for local development, testing, and enhanced security scenarios where network exposure is a concern
  2. HTTP: Ideal for stateless operations, simple integrations, and when working with existing HTTP infrastructure
When configuring your mcp_use environment, you can specify the connection type in your configuration file as shown in the examples above.

​
Using Connection Types

Connection types are automatically inferred from your configuration file based on the parameters provided: For example:
  • If your configuration includes command and args, a local STDIO connection will be used
  • If your configuration has a url starting with http:// or https://, an HTTP connection will be used
This automatic inference simplifies the configuration process and ensures the appropriate connection type is used without requiring explicit specification. For more details on connection configuration, see the Configuration Guide.