Struct Client 

pub struct Client { /* private fields */ }

Cheaply-cloneable MCP client. Cloning shares the same underlying transport via Arc. After Client::shutdown the transport is gone and further calls return ClientError::Request.

Implementations

impl Client

pub async fn connect(target: &Target) -> Result<Self>

pub async fn reconnect(&self) -> Result<()>

Tears down the current transport and opens a new one. Other tasks holding a &self reference will see the new transport on their next call. Phase E1 changed this from &mut self to &self so callers can recover after a fault without exclusive ownership of the Client.

pub async fn list_tools(&self) -> Result<Vec<Tool>>

pub async fn server_capabilities(&self) -> Option<ServerCapabilities>

Returns a clone of the server’s announced ServerCapabilities from the initial initialize handshake, or None if the client has been shut down or the handshake hadn’t completed.

Per MCP spec, clients should not call resources/list or prompts/list against a server that didn’t declare the corresponding capability — doing so produces a noisy -32601 method not found from compliant servers. Use this to gate optional listing calls.

pub async fn list_resources(&self) -> Result<Vec<Resource>>

Lists the server’s resources. Returns Ok(vec![]) (silently) when the server didn’t declare the resources capability at init time — this avoids spamming a -32601 method not found failure for servers that legitimately don’t expose resources. Callers needing to distinguish “not advertised” from “empty” should check Self::server_capabilities first.

pub async fn list_prompts(&self) -> Result<Vec<Prompt>>

Lists the server’s prompts. Same capability-aware short-circuit as Self::list_resources: returns Ok(vec![]) when the server didn’t declare the prompts capability.

pub async fn call_tool( &self, name: &str, arguments: Value, timeout: Duration, ) -> CallOutcome

pub async fn shutdown(&self) -> Result<()>

Shuts the underlying transport down. After this call other clones of this Client keep working semantically but return ProtocolError on every method (the transport is gone).

pub fn target(&self) -> &Target

Trait Implementations

impl Clone for Client

fn clone(&self) -> Client

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl McpExec for Client

fn list_tools<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<Vec<Tool>, ClientError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Lists every tool exposed by the server.

fn call_tool<'life0, 'life1, 'async_trait>( &'life0 self, name: &'life1 str, arguments: Value, timeout: Duration, ) -> Pin<Box<dyn Future<Output = CallOutcome> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Calls a tool, applying timeout. Returns a CallOutcome that the caller pattern-matches; this method itself never errors.

fn reconnect<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<(), ClientError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Tears down the transport and rebuilds it. Used after a hang/crash so subsequent calls can succeed. Concurrent callers see either the old or the new transport, never a torn state.