io.modelcontextprotocol.server

Class McpSyncServerExchange

java.lang.Object

io.modelcontextprotocol.server.McpSyncServerExchange

public class McpSyncServerExchange
extends Object

Represents a synchronous exchange with a Model Context Protocol (MCP) client. The exchange provides methods to interact with the client and query its capabilities.

Author:

Dariusz Jędrzejczyk, Christian Tzolov

Constructor Summary

Constructors

Constructor and Description
McpSyncServerExchange(McpAsyncServerExchange exchange) Create a new synchronous exchange with the client using the provided asynchronous implementation as a delegate.

Method Summary

Modifier and Type	Method and Description
McpSchema.ElicitResult	createElicitation(McpSchema.ElicitRequest elicitRequest) Creates a new elicitation.
McpSchema.CreateMessageResult	createMessage(McpSchema.CreateMessageRequest createMessageRequest) Create a new message using the sampling capabilities of the client.
McpSchema.ClientCapabilities	getClientCapabilities() Get the client capabilities that define the supported features and functionality.
McpSchema.Implementation	getClientInfo() Get the client implementation information.
McpSchema.ListRootsResult	listRoots() Retrieves the list of all roots provided by the client.
McpSchema.ListRootsResult	listRoots(String cursor) Retrieves a paginated list of roots provided by the client.
void	loggingNotification(McpSchema.LoggingMessageNotification loggingMessageNotification) Send a logging message notification to the client.
Object	ping() Sends a synchronous ping request to the client.
void	progressNotification(McpSchema.ProgressNotification progressNotification) Sends a notification to the client that the current progress status has changed for long-running operations.
String	sessionId() Provides the Session ID
McpTransportContext	transportContext() Provides the McpTransportContext associated with the transport layer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

McpSyncServerExchange

public McpSyncServerExchange(McpAsyncServerExchange exchange)

Create a new synchronous exchange with the client using the provided asynchronous implementation as a delegate.

Parameters:

exchange - The asynchronous exchange to delegate to.

Method Detail

sessionId

public String sessionId()

Provides the Session ID

Returns:

session ID

getClientCapabilities

public McpSchema.ClientCapabilities getClientCapabilities()

Get the client capabilities that define the supported features and functionality.

Returns:

The client capabilities

getClientInfo

public McpSchema.Implementation getClientInfo()

Get the client implementation information.

Returns:

The client implementation details

transportContext

public McpTransportContext transportContext()

Provides the McpTransportContext associated with the transport layer. For HTTP transports it can contain the metadata associated with the HTTP request that triggered the processing.

Returns:

the transport context object

createMessage

public McpSchema.CreateMessageResult createMessage(McpSchema.CreateMessageRequest createMessageRequest)

Create a new message using the sampling capabilities of the client. The Model Context Protocol (MCP) provides a standardized way for servers to request LLM sampling (“completions” or “generations”) from language models via clients. This flow allows clients to maintain control over model access, selection, and permissions while enabling servers to leverage AI capabilities—with no server API keys necessary. Servers can request text or image-based interactions and optionally include context from MCP servers in their prompts.

Parameters:

createMessageRequest - The request to create a new message

Returns:

A result containing the details of the sampling response

See Also:

McpSchema.CreateMessageRequest, McpSchema.CreateMessageResult, Sampling Specification

createElicitation

public McpSchema.ElicitResult createElicitation(McpSchema.ElicitRequest elicitRequest)

Creates a new elicitation. MCP provides a standardized way for servers to request additional information from users through the client during interactions. This flow allows clients to maintain control over user interactions and data sharing while enabling servers to gather necessary information dynamically. Servers can request structured data from users with optional JSON schemas to validate responses.

Parameters:

elicitRequest - The request to create a new elicitation

Returns:

A result containing the elicitation response.

See Also:

McpSchema.ElicitRequest, McpSchema.ElicitResult, Elicitation Specification

listRoots

public McpSchema.ListRootsResult listRoots()

Retrieves the list of all roots provided by the client.

Returns:

The list of roots result.

listRoots

public McpSchema.ListRootsResult listRoots(String cursor)

Retrieves a paginated list of roots provided by the client.

Parameters:

cursor - Optional pagination cursor from a previous list request

Returns:

The list of roots result

loggingNotification

public void loggingNotification(McpSchema.LoggingMessageNotification loggingMessageNotification)

Send a logging message notification to the client. Messages below the current minimum logging level will be filtered out.

Parameters:

loggingMessageNotification - The logging message to send

progressNotification

public void progressNotification(McpSchema.ProgressNotification progressNotification)

Sends a notification to the client that the current progress status has changed for long-running operations.

Parameters:

progressNotification - The progress notification to send

ping

public Object ping()

Sends a synchronous ping request to the client.

Returns: