Module http 

HTTP transport for FastMCP.

This module provides HTTP-based transport for MCP servers, enabling web-based deployments without relying on stdio or WebSockets.

Modes

The HTTP transport supports two modes:

• Stateless: Each HTTP request contains a single JSON-RPC message and receives a single response. No session state is maintained between requests.

• Streamable: Long-lived connections using HTTP streaming (chunked transfer) for bidirectional communication. Supports Server-Sent Events (SSE) for server-to-client notifications.

Integration

This transport is designed to integrate with any HTTP server framework. It provides:

• HttpRequestHandler: Processes incoming HTTP requests containing JSON-RPC messages
• HttpTransport: Full transport implementation for HTTP connections
• StreamableHttpTransport: Streaming transport for long-lived connections

Example

use fastmcp_transport::http::{HttpRequestHandler, HttpRequest, HttpResponse};

let handler = HttpRequestHandler::new();

// In your HTTP server's request handler:
fn handle_mcp_request(http_req: YourHttpRequest) -> YourHttpResponse {
    let request = HttpRequest {
        method: http_req.method(),
        path: http_req.path(),
        headers: http_req.headers(),
        body: http_req.body(),
    };

    let mcp_response = handler.handle(&cx, request)?;

    YourHttpResponse::new()
        .status(mcp_response.status)
        .header("Content-Type", &mcp_response.content_type)
        .body(mcp_response.body)
}

Structs

HttpHandlerConfig

Configuration for the HTTP request handler.

HttpRequest

Incoming HTTP request.

HttpRequestHandler

Handles HTTP requests containing MCP JSON-RPC messages.

HttpResponse

Outgoing HTTP response.

HttpSession

HTTP session for maintaining state across requests.

HttpStatus

HTTP status code.

HttpTransport

HTTP transport for stateless MCP communication.

SessionStore

Session store for HTTP sessions.

StreamableHttpTransport

Streaming HTTP transport for long-lived MCP connections.

Enums

HttpError

HTTP transport error.

HttpMethod

HTTP method.