mcp::server::ClientPeer Class Reference

Non-owning handle for the client associated with a server session. More...

#include <peer.hpp>

Public Member Functions
	ClientPeer (Transport *transport=nullptr, std::string session_id={}, std::weak_ptr< void > transport_lifetime={}) noexcept
	Construct a peer from a borrowed transport pointer.
bool	available () const noexcept
	Report whether this peer has a transport to send through.
bool	supports_roots () const noexcept
	Report whether the client advertised roots/list support.
bool	supports_sampling_tools () const noexcept
	Report whether the client advertised sampling support.
bool	supports_elicitation_form () const noexcept
	Report whether the client advertised form elicitation support.
bool	supports_elicitation_url () const noexcept
	Report whether the client advertised URL elicitation support.
bool	supports_elicitation () const noexcept
	Report whether the client supports any elicitation mode.
bool	supports_task_list () const noexcept
	Report whether the client advertised task listing support.
bool	supports_task_cancel () const noexcept
	Report whether the client advertised task cancellation support.
bool	supports_tasks () const noexcept
	Report whether the client advertised any task support.
core::Result< core::Unit >	notify_cancelled (protocol::RequestId request_id, std::string reason={}) const
	Notify the client that a request was cancelled.
RequestHandle< protocol::Json >	request_async (std::string method, protocol::Json params=protocol::Json::object(), RequestOptions options={}) const
	Send a raw JSON-RPC request to the client and return a handle.
core::Result< protocol::Json >	request (std::string method, protocol::Json params=protocol::Json::object()) const
	Send a raw JSON-RPC request to the client.
core::Result< protocol::RootsListResult >	list_roots () const
	Request the client's root list.
RequestHandle< protocol::RootsListResult >	list_roots_async (RequestOptions options={}) const
	Request the client's root list asynchronously.
core::Result< protocol::CreateMessageResult >	create_message (const protocol::CreateMessageParams &params) const
	Ask the client to create a sampled message.
RequestHandle< protocol::CreateMessageResult >	create_message_async (const protocol::CreateMessageParams &params, RequestOptions options={}) const
	Ask the client to create a sampled message asynchronously.
core::Result< protocol::CreateElicitationResult >	create_elicitation (const protocol::CreateElicitationRequestParam &params) const
	Ask the client to perform an elicitation flow.
RequestHandle< protocol::CreateElicitationResult >	create_elicitation_async (const protocol::CreateElicitationRequestParam &params, RequestOptions options={}) const
	Ask the client to perform an elicitation flow asynchronously.
template<class T >
core::Result< T >	elicit (std::string message, RequestOptions options={}) const
	Ask the client for typed form input using SchemaTraits<T>.
template<class T >
core::Result< T >	elicit (std::string message, protocol::ElicitationSchema schema, RequestOptions options={}) const
	Ask the client for typed form input using an explicit schema.
template<class T >
RequestHandle< T >	elicit_async (std::string message, RequestOptions options={}) const
	Async typed form elicitation using SchemaTraits<T>.
template<class T >
RequestHandle< T >	elicit_async (std::string message, protocol::ElicitationSchema schema, RequestOptions options={}) const
	Async typed form elicitation using an explicit schema.
core::Result< core::Unit >	elicit_url (std::string message, std::string elicitation_id, std::string url, RequestOptions options={}) const
	Ask the client to complete a URL-based elicitation flow.
RequestHandle< core::Unit >	elicit_url_async (std::string message, std::string elicitation_id, std::string url, RequestOptions options={}) const
	Async URL elicitation helper.
core::Result< std::vector< protocol::Task > >	list_tasks () const
	Request one page of tasks from the client.
core::Result< std::vector< protocol::Task > >	list_all_tasks () const
	Request all client task pages by following cursors.
core::Result< protocol::Task >	get_task (std::string_view task_id) const
	Request a single task by id.
core::Result< protocol::Task >	cancel_task (std::string_view task_id) const
	Request cancellation of a client task.
core::Result< protocol::Json >	task_result (std::string_view task_id) const
	Request the result payload for a completed client task.
core::Result< core::Unit >	notify_elicitation_complete (std::string elicitation_id) const
	Notify the client that an elicitation flow has completed.

Detailed Description

Non-owning handle for the client associated with a server session.

ClientPeer wraps a borrowed Transport pointer from SessionContext. It is cheap to copy and does not extend the lifetime of either the transport or the underlying MCP session. Use available() before optional peer operations when the context may not have come from a live transport.

New code may prefer the SessionClient or ClientHandle aliases to avoid confusing this session-bound handle with the top-level mcp::ClientPeer.

Methods return core::Result and never throw intentionally. Transport failures, protocol error responses, unsupported client capabilities, and response deserialization failures are propagated as core::Error values.

Constructor & Destructor Documentation

ClientPeer()

mcp::server::ClientPeer::ClientPeer ( Transport *  transport = nullptr, std::string  session_id = {}, std::weak_ptr< void >  transport_lifetime = {}  )

inlineexplicitnoexcept

Construct a peer from a borrowed transport pointer.

Parameters

transport	Transport used for outbound messages; may be nullptr.
session_id	Session identifier used for capability lookup.
transport_lifetime	Lifetime token for the borrowed transport; when expired, the peer reports unavailable instead of using the pointer.

Member Function Documentation

cancel_task()

core::Result< protocol::Task > mcp::server::ClientPeer::cancel_task ( std::string_view  task_id ) const

inline

Request cancellation of a client task.

Parameters

task_id

Client task identifier.

Returns

Parsed task state returned by the client, or a core::Error.

create_elicitation()

core::Result< protocol::CreateElicitationResult > mcp::server::ClientPeer::create_elicitation ( const protocol::CreateElicitationRequestParam &  params ) const

inline

Ask the client to perform an elicitation flow.

Parameters

params

Elicitation request parameters including mode.

Returns

Parsed elicitation result, or a core::Error when the requested mode is unsupported, delivery fails, the client returns an error, or the response cannot be parsed.

create_message()

core::Result< protocol::CreateMessageResult > mcp::server::ClientPeer::create_message ( const protocol::CreateMessageParams &  params ) const

inline

Ask the client to create a sampled message.

Parameters

params

Sampling request parameters.

Returns

Parsed sampling result, or a core::Error for unsupported capability, transport failure, protocol error, or parse failure.

elicit()

template<class T >

core::Result< T > mcp::server::ClientPeer::elicit ( std::string  message, RequestOptions  options = {}  ) const

inline

Ask the client for typed form input using SchemaTraits<T>.

Primitive T schemas are wrapped as a required value field. Object schemas generated by SchemaTraits<T> are used directly and decoded from the accepted content object.

get_task()

core::Result< protocol::Task > mcp::server::ClientPeer::get_task ( std::string_view  task_id ) const

inline

Request a single task by id.

Parameters

task_id

Client task identifier.

Returns

Parsed task, or a core::Error from transport, protocol, or parsing.

list_all_tasks()

core::Result< std::vector< protocol::Task > > mcp::server::ClientPeer::list_all_tasks ( ) const

inline

Request all client task pages by following cursors.

Returns

Aggregated tasks in server-observed page order, or the first core::Error encountered.

list_roots()

core::Result< protocol::RootsListResult > mcp::server::ClientPeer::list_roots ( ) const

inline

Request the client's root list.

Returns

Parsed roots/list result, or a core::Error if the client did not advertise roots support, transport delivery fails, or parsing fails.

list_tasks()

core::Result< std::vector< protocol::Task > > mcp::server::ClientPeer::list_tasks ( ) const

inline

Request one page of tasks from the client.

Returns

Tasks from the first returned page, or a core::Error from transport, protocol, or parsing.

notify_elicitation_complete()

core::Result< core::Unit > mcp::server::ClientPeer::notify_elicitation_complete ( std::string  elicitation_id ) const

inline

Notify the client that an elicitation flow has completed.

Parameters

elicitation_id

Identifier of the elicitation flow.

Returns

core::Unit on delivery, or a core::Error when the peer is unavailable or the transport cannot send the notification.

request()

core::Result< protocol::Json > mcp::server::ClientPeer::request ( std::string  method, protocol::Json  params = protocol::Json::object()  ) const

inline

Send a raw JSON-RPC request to the client.

Parameters

method	JSON-RPC method name.
params	JSON-RPC params payload. Defaults to an empty object.

Returns

The response result payload, or a core::Error when the peer is unavailable, the transport fails, the response is an error, or the response has no result.

Note

On HTTP transports this may block until the client posts the correlated response. The generated request id is process-global.

request_async()

RequestHandle< protocol::Json > mcp::server::ClientPeer::request_async ( std::string  method, protocol::Json  params = protocol::Json::object(), RequestOptions  options = {}  ) const

inline

Send a raw JSON-RPC request to the client and return a handle.

Parameters

method	JSON-RPC method name.
params	JSON-RPC params payload. Defaults to an empty object.
options	Optional timeout and metadata.

Returns

A handle that can await the response or send cancellation.

task_result()

core::Result< protocol::Json > mcp::server::ClientPeer::task_result ( std::string_view  task_id ) const

inline

Request the result payload for a completed client task.

Parameters

task_id

Client task identifier.

Returns

Raw JSON result payload, or a core::Error.

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The documentation for this class was generated from the following file:

• sdk/server/include/cxxmcp/server/peer.hpp