Struct McpClient

pub struct McpClient { /* private fields */ }

MCP client

MCP server’s methods to call and respond to client feature requests from the server.

To create an McpClient, use the with_server method or McpClientBuilder. The method to create an McpClient performs an initialize request to the server and returns control when the request completes.

Example

use mcp_attr::client::McpClient;
use mcp_attr::schema::{ListPromptsRequestParams, ListResourcesRequestParams, CallToolRequestParams};
use mcp_attr::server::{McpServer, mcp_server};

struct MyServer;

#[mcp_server]
impl McpServer for MyServer {}

let server = MyServer;
let client = McpClient::with_server(server).await?;

// Get prompt list
let prompts = client.prompts_list(None).await?;

// Get resource list
let resources = client.resources_list(None).await?;

// Call tool
let params = CallToolRequestParams {
    name: "tool_name".to_string(),
    arguments: Some(serde_json::Map::new()),
};
let result = client.tools_call(params).await?;

Implementations

impl McpClient

pub async fn with_server(server: impl McpServer) -> SessionResult<Self>

Connects to the specified McpServer in-process

Performs an initialize request to the server and returns the result

pub async fn initialize( session: Session, p: InitializeRequestParams, ) -> SessionResult<Self>

Connects to an MCP server using the specified JSON RPC Session

This Session uses the values returned from McpClientBuilder::build_raw.

Performs an initialize request to the server and returns the result

pub fn session(&self) -> &Session

Gets the JSON RPC Session

pub fn instructions(&self) -> Option<&str>

Gets the instructions obtained from the initialize request response

pub fn server_info(&self) -> &Implementation

Gets the server_info obtained from the initialize request response

pub async fn prompts_list( &self, params: Option<ListPromptsRequestParams>, ) -> SessionResult<ListPromptsResult>

Calls prompts/list

pub async fn prompts_get( &self, params: GetPromptRequestParams, ) -> SessionResult<GetPromptResult>

Calls prompts/get

pub async fn resources_list( &self, params: Option<ListResourcesRequestParams>, ) -> SessionResult<ListResourcesResult>

Calls resources/list

pub async fn resources_templates_list( &self, params: Option<ListResourceTemplatesRequestParams>, ) -> SessionResult<ListResourceTemplatesResult>

Calls resources/templates/list

pub async fn resources_read( &self, params: ReadResourceRequestParams, ) -> SessionResult<ReadResourceResult>

Calls resources/read

pub async fn tools_list( &self, params: Option<ListToolsRequestParams>, ) -> SessionResult<ListToolsResult>

Calls tools/list

pub async fn tools_call( &self, params: CallToolRequestParams, ) -> SessionResult<CallToolResult>

Calls tools/call

pub async fn completion_complete( &self, params: CompleteRequestParams, ) -> SessionResult<CompleteResult>

Calls completion/complete

pub async fn ping(&self) -> SessionResult<()>

Calls ping