Module capabilities

turbomcp_server

Module capabilities 

Source
Expand description

Server-to-client request adapter for bidirectional MCP communication.

This module provides the adapter that bridges the ServerToClientRequests trait (defined in turbomcp-protocol) to the concrete BidirectionalRouter implementation, enabling tools to make server-initiated requests to clients.

§Architecture

Tool Handler (ctx.create_message)
    ↓
ServerToClientRequests trait (turbomcp-protocol) ← TYPE-SAFE INTERFACE
    ↓
ServerToClientAdapter (this module) ← THE BRIDGE
    ↓
BidirectionalRouter (turbomcp-server)
    ↓
ServerRequestDispatcher (transport abstraction)
    ↓
Transport Layer (stdio, HTTP, WebSocket, etc.)

§Design Improvements (v2.0.0)

This adapter was redesigned to leverage the new type-safe trait:

  • Before: Double serialization (typed → JSON → typed → JSON)
  • After: Zero serialization (typed → typed)
  • Before: Cannot propagate RequestContext
  • After: Full context propagation for tracing and attribution
  • Before: Generic Box<dyn Error> return type
  • After: Structured ServerError with pattern matching

§Bug Fix History

v1.x: Fixed critical bug where RequestContext.server_capabilities was never populated, causing all sampling/elicitation requests to fail.

v2.0: Improved trait design to eliminate double serialization and enable context propagation.

Structs§

ServerToClientAdapter
Adapter that implements the ServerToClientRequests trait by delegating to BidirectionalRouter.