Class DefaultMcpClient

java.lang.Object

dev.langchain4j.mcp.client.DefaultMcpClient

All Implemented Interfaces:

McpClient, AutoCloseable

public class DefaultMcpClient
extends Object
implements McpClient

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	DefaultMcpClient.Builder

Constructor Summary

Constructors

Constructor	Description
DefaultMcpClient(DefaultMcpClient.Builder builder)

Method Summary

Modifier and Type	Method	Description
void	checkHealth()	Performs a health check that returns normally if the MCP server is reachable and properly responding to ping requests.
void	close()
void	evictToolListCache()	Evicts the tool list cache, forcing the next call to listTools() to retrieve a fresh list of tools from the MCP server.
ToolExecutionResult	executeTool(ToolExecutionRequest executionRequest)	Executes a tool on the MCP server and returns the result.
McpGetPromptResult	getPrompt(String name, Map<String,Object> arguments)	Render the contents of a prompt.
String	key()	Returns the unique key of this client.
List<McpPrompt>	listPrompts()	Obtain a list of prompts available on the MCP server.
List<McpResource>	listResources()	Obtains the current list of resources available on the MCP server.
List<McpResourceTemplate>	listResourceTemplates()	Obtains the current list of resource templates (dynamic resources) available on the MCP server.
List<ToolSpecification>	listTools()	Obtains a list of tools from the MCP server.
McpReadResourceResult	readResource(String uri)	Retrieves the contents of the resource with the specified URI.
void	setRoots(List<McpRoot> roots)	Sets the roots that are made available to the server upon its request.

Methods inherited from class Object

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

Constructor Details

DefaultMcpClient

public DefaultMcpClient(DefaultMcpClient.Builder builder)

Method Details

key

public String key()

Description copied from interface: McpClient

Returns the unique key of this client.

Specified by:

key in interface McpClient

listTools

public List<ToolSpecification> listTools()

Description copied from interface: McpClient

Obtains a list of tools from the MCP server.

Specified by:

listTools in interface McpClient

evictToolListCache

public void evictToolListCache()

Evicts the tool list cache, forcing the next call to listTools() to retrieve a fresh list of tools from the MCP server.

executeTool

public ToolExecutionResult executeTool(ToolExecutionRequest executionRequest)

Description copied from interface: McpClient

Executes a tool on the MCP server and returns the result. Currently, this expects a tool execution to only contain text-based results or JSON structured content.

Specified by:

executeTool in interface McpClient

listResources

public List<McpResource> listResources()

Description copied from interface: McpClient

Obtains the current list of resources available on the MCP server.

Specified by:

listResources in interface McpClient

readResource

public McpReadResourceResult readResource(String uri)

Description copied from interface: McpClient

Retrieves the contents of the resource with the specified URI. This also works for dynamic resources (templates).

Specified by:

readResource in interface McpClient

listPrompts

public List<McpPrompt> listPrompts()

Description copied from interface: McpClient

Obtain a list of prompts available on the MCP server.

Specified by:

listPrompts in interface McpClient

getPrompt

public McpGetPromptResult getPrompt(String name,
 Map<String,Object> arguments)

Description copied from interface: McpClient

Render the contents of a prompt.

Specified by:

getPrompt in interface McpClient

checkHealth

public void checkHealth()

Description copied from interface: McpClient

Performs a health check that returns normally if the MCP server is reachable and properly responding to ping requests. If this method throws an exception, the health of this MCP client is considered degraded.

Specified by:

checkHealth in interface McpClient

setRoots

public void setRoots(List<McpRoot> roots)

Description copied from interface: McpClient

Sets the roots that are made available to the server upon its request. After calling this method, the client also sends a `notifications/roots/list_changed` message to the server.

Specified by:

setRoots in interface McpClient

listResourceTemplates

public List<McpResourceTemplate> listResourceTemplates()

Description copied from interface: McpClient

Obtains the current list of resource templates (dynamic resources) available on the MCP server.

Specified by:

listResourceTemplates in interface McpClient

close

public void close()

Specified by:

close in interface AutoCloseable