Module io.modelcontextprotocol.sdk.mcp

Package io.modelcontextprotocol.spec

Interface McpClientTransport

All Superinterfaces:

McpTransport

All Known Implementing Classes:

HttpClientSseClientTransport, HttpClientStreamableHttpTransport, StdioClientTransport

public interface McpClientTransport
extends McpTransport

Interface for the client side of the McpTransport. It allows setting handlers for messages that are incoming from the MCP server and hooking in to exceptions raised on the transport layer.

Author:

Christian Tzolov, Dariusz Jędrzejczyk

Method Summary

Modifier and Type	Method	Description
reactor.core.publisher.Mono<Void>	connect(Function<reactor.core.publisher.Mono<McpSchema.JSONRPCMessage>,reactor.core.publisher.Mono<McpSchema.JSONRPCMessage>> handler)	Used to register the incoming messages' handler and potentially (eagerly) connect to the server.
default void	setExceptionHandler(Consumer<Throwable> handler)	Sets the exception handler for exceptions raised on the transport layer.

Methods inherited from interface io.modelcontextprotocol.spec.McpTransport

close, closeGracefully, protocolVersions, sendMessage, unmarshalFrom

Method Details

connect

reactor.core.publisher.Mono<Void> connect(Function<reactor.core.publisher.Mono<McpSchema.JSONRPCMessage>,reactor.core.publisher.Mono<McpSchema.JSONRPCMessage>> handler)

Used to register the incoming messages' handler and potentially (eagerly) connect to the server.

Parameters:

handler - a transformer for incoming messages

Returns:

a Mono that terminates upon successful client setup. It can mean establishing a connection (which can be later disposed) but it doesn't have to, depending on the transport type. The successful termination of the returned Mono simply means the client can now be used. An error can be retried according to the application requirements.

setExceptionHandler

default void setExceptionHandler(Consumer<Throwable> handler)

Sets the exception handler for exceptions raised on the transport layer.

Parameters:

handler - Allows reacting to transport level exceptions by the higher layers