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
Task management with anyio task groups
Ability to send multiple notifications over time to the client
Proper resource cleanup and lifespan management
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