Struct Client 

pub struct Client { /* private fields */ }

Claude Messages API client.

Implementations

impl Client

pub fn with_token(_token: impl Into<String>) -> Self

Create a new client with a single token (no pool/rotation).

pub fn builder() -> ClientBuilder

Create a client builder.

pub async fn message( &self, model: &str, messages: &[Message], max_tokens: u32, ) -> Result<MessagesResponse>

Send a Messages API request.

pub async fn message_with_system( &self, model: &str, messages: &[Message], max_tokens: u32, system: Option<&str>, ) -> Result<MessagesResponse>

Send a Messages API request with system prompt.

pub async fn message_with_tools( &self, model: &str, messages: &[Message], max_tokens: u32, system: Option<&str>, tools: Option<&[Tool]>, ) -> Result<MessagesResponse>

Send a Messages API request with system prompt and tools.

pub async fn run_agent_loop( &self, model: &str, system: &str, initial_message: &str, tools: &[Tool], max_turns: u32, tool_handler: &dyn ToolHandler, ) -> Result<AgentLoopResult>

Run an agent loop with tool use support.

This method sends the initial message, handles tool calls via the handler, and continues the conversation until Claude stops calling tools or max_turns is reached.

Arguments

• model: The model to use (e.g., “claude-sonnet-4-5”)
• system: System prompt
• initial_message: The user’s initial request
• tools: Tool definitions
• max_turns: Maximum conversation turns (each turn = one API call)
• tool_handler: Handler for executing tools

Returns

An AgentLoopResult with final text, total tokens, turns used, and tool calls.

Trait Implementations

impl Debug for Client

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.