entropic::ExternalMCPClient Class Reference

Client for an external MCP server (stdio or SSE). More...

#include <entropic/mcp/external_client.h>

Public Member Functions
	ExternalMCPClient (std::string name, std::unique_ptr< Transport > transport)
	Construct with name and transport.
bool	connect ()
	Connect: open transport + MCP initialize + tools/list.
void	disconnect ()
	Disconnect: close transport.
std::string	list_tools () const
	List tools as JSON array string (cached).
std::string	execute (const std::string &tool_name, const std::string &args_json)
	Execute a tool call via the external server.
std::pair< std::vector< std::string >, std::vector< std::string > >	refresh_tools ()
	Re-query tools/list and diff against cache.
bool	is_connected () const
	Check connection state.
const std::string &	name () const
	Get server name.
void	interrupt ()
	Abort any pending execute() by interrupting the transport.

Detailed Description

Client for an external MCP server (stdio or SSE).

Owns a Transport instance. Handles MCP protocol negotiation, tool list caching, tool name prefixing, and response sanitization.

Security

External server responses have their "directives" array stripped. External servers CANNOT inject delegate, stop_processing, phase_change, or other engine-level directives.

Version

1.8.7

Definition at line 41 of file external_client.h.

Constructor & Destructor Documentation

ExternalMCPClient()

entropic::ExternalMCPClient::ExternalMCPClient	(	std::string	name,
		std::unique_ptr< Transport >	transport
	)

Construct with name and transport.

Parameters

name	Server name (unique key, used as tool prefix).
transport	Ownership transferred.

Version

1.8.7

Parameters

name	Server name.
transport	Ownership transferred. @dg_internal

Version

1.8.7

Definition at line 27 of file external_client.cpp.

Member Function Documentation

connect()

bool entropic::ExternalMCPClient::connect

(

)

Connect: open transport + MCP initialize + tools/list.

Connect: open transport, initialize, query tools.

Returns

true on success.

Version

1.8.7

The MCP handshake in order — transport open, initialize, tools/list.

Returns

true when the transport opened and initialize succeeded; false otherwise. A failed tools/list is NOT fatal: the client stays connected with zero tools and a warning, so a server that is up but tool-less does not read as down. @req REQ-MCP-025

Version

1.8.7

Definition at line 45 of file external_client.cpp.

disconnect()

void entropic::ExternalMCPClient::disconnect

(

)

Disconnect: close transport.

Disconnect: close transport, clear cache.

Version

1.8.7

@dg_internal

Version

1.8.7

Definition at line 72 of file external_client.cpp.

execute()

std::string entropic::ExternalMCPClient::execute	(	const std::string &	tool_name,
		const std::string &	args_json
	)

Execute a tool call via the external server.

Parameters

tool_name	Local name (without server prefix).
args_json	JSON arguments string.

Returns

ServerResponse JSON envelope (directives always empty).

Version

1.8.7

Parameters

tool_name	Local name (without server prefix).
args_json	JSON arguments; unparseable arguments degrade to an empty object rather than throwing.

Returns

A ServerResponse JSON envelope whose directives array is ALWAYS empty — see build_response. A disconnected transport or an empty (timed-out) response yields an is_error envelope instead of a hang. @req REQ-MCP-025 @req REQ-MCP-002

Version

1.8.7

Definition at line 107 of file external_client.cpp.

interrupt()

void entropic::ExternalMCPClient::interrupt ( )

inline

Abort any pending execute() by interrupting the transport.

Delegates to Transport::interrupt(). Safe to call concurrently from the engine's interrupt thread. (P1-10, 2.0.6-rc16)

@utility

Version

2.0.6-rc16

Definition at line 114 of file external_client.h.

is_connected()

bool entropic::ExternalMCPClient::is_connected

(

)

const

Check connection state.

Check connection state via transport.

Returns

true if transport is connected.

Version

1.8.7

Returns

true if connected. @dg_internal

Version

1.8.7

Definition at line 193 of file external_client.cpp.

list_tools()

std::string entropic::ExternalMCPClient::list_tools

(

)

const

List tools as JSON array string (cached).

List tools as JSON array string (cached, prefixed).

Returns

JSON array of tool definitions with prefixed names.

Version

1.8.7

Returns

The cached tool descriptors with names already <server>.<tool>-prefixed, so ServerManager can concatenate them without re-prefixing; "[]" when disconnected. @req REQ-MCP-025 @req REQ-MCP-007

Version

1.8.7

Definition at line 89 of file external_client.cpp.

name()

const std::string & entropic::ExternalMCPClient::name ( ) const

inline

Get server name.

Returns

Server name string. @utility

Version

1.8.7

Definition at line 103 of file external_client.h.

refresh_tools()

std::pair< std::vector< std::string >, std::vector< std::string > > entropic::ExternalMCPClient::refresh_tools

(

)

Re-query tools/list and diff against cache.

Returns

Pair of (added_names, removed_names).

Version

1.8.7

Called after a successful reconnect so the model's tool list tracks a server that changed while it was down.

Returns

A pair of (added, removed) fully-qualified tool names; both empty when the server's surface is unchanged. @req REQ-MCP-025

Version

2.3.7

Definition at line 168 of file external_client.cpp.

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

• entropic/mcp/external_client.h
• mcp/external_client.cpp