modelcontextprotocol--python-sdk/examples/servers/simple-streamablehttp

MCP Simple StreamableHttp Server Example

A simple MCP server example demonstrating the StreamableHttp transport, which enables HTTP-based communication with MCP servers using streaming.

Features

• Uses the StreamableHTTP transport for server-client communication
• Supports REST API operations (POST, GET, DELETE) for /mcp endpoint
• Ability to send multiple notifications over time to the client
• Resumability support via InMemoryEventStore

Usage

Start the server on the default or custom port:

# Using custom port
uv run mcp-simple-streamablehttp --port 3000

# Custom logging level
uv run mcp-simple-streamablehttp --log-level DEBUG

# Enable JSON responses instead of SSE streams
uv run mcp-simple-streamablehttp --json-response

The server exposes a tool named "start-notification-stream" that accepts three arguments:

• interval: Time between notifications in seconds (e.g., 1.0)
• count: Number of notifications to send (e.g., 5)
• caller: Identifier string for the caller

Resumability Support

This server includes resumability support through the InMemoryEventStore. This enables clients to:

• Reconnect to the server after a disconnection
• Resume event streaming from where they left off using the Last-Event-ID header

The server will:

• Generate unique event IDs for each SSE message
• Store events in memory for later replay
• Replay missed events when a client reconnects with a Last-Event-ID header

Note: The InMemoryEventStore is designed for demonstration purposes only. For production use, consider implementing a persistent storage solution.

Client

You can connect to this server using an HTTP client, for now only Typescript SDK has streamable HTTP client examples or you can use Inspector