Struct MessagesResource

pub struct MessagesResource<'a> { /* private fields */ }

Messages API resource for interacting with Claude

Implementations

impl<'a> MessagesResource<'a>

pub fn new(client: &'a Anthropic) -> Self

Create a new Messages resource

pub async fn create(&self, params: MessageCreateParams) -> Result<Message>

Create a message with Claude

Send a structured list of input messages with text and/or image content, and Claude will generate the next message in the conversation.

Example

use anthropic_sdk::{Anthropic, types::MessageCreateBuilder};
 
let client = Anthropic::from_env()?;
 
let message = client.messages().create(
    MessageCreateBuilder::new("claude-3-5-sonnet-latest", 1024)
        .user("Hello, Claude!")
        .build()
).await?;
 
println!("Claude responded: {:?}", message.content);

pub async fn create_stream( &self, params: MessageCreateParams, ) -> Result<MessageStream>

Create a streaming message with Claude

Send a message request and receive a real-time stream of the response. This allows you to process Claude’s response as it’s being generated.

Example

use anthropic_sdk::{Anthropic, MessageCreateBuilder};
use futures::StreamExt;
 
let client = Anthropic::from_env()?;
 
let stream = client.messages().create_stream(
    MessageCreateBuilder::new("claude-3-5-sonnet-latest", 1024)
        .user("Write a story about AI")
        .stream(true)
        .build()
).await?;
 
// Option 1: Use callbacks
let final_message = stream
    .on_text(|delta, _| print!("{}", delta))
    .on_error(|error| eprintln!("Error: {}", error))
    .final_message().await?;
 
// Option 2: Manual iteration
while let Some(event) = stream.next().await {
    // Process each event as needed
}

pub async fn stream(&self, params: MessageCreateParams) -> Result<MessageStream>

Create a streaming message using the builder pattern

This is a convenience method that provides an ergonomic API for creating streaming messages.

Example

use anthropic_sdk::Anthropic;
 
let client = Anthropic::from_env()?;
 
let final_message = client.messages()
    .create_with_builder("claude-3-5-sonnet-latest", 1024)
    .user("Write a poem about the ocean")
    .system("You are a creative poet.")
    .temperature(0.8)
    .stream()
    .await?
    .on_text(|delta, _| print!("{}", delta))
    .final_message()
    .await?;

pub fn create_with_builder( &'a self, model: impl Into<String>, max_tokens: u32, ) -> MessageCreateBuilderWithClient<'a>

Create a message using the builder pattern

This is a convenience method that provides an ergonomic API for creating messages.

Example

use anthropic_sdk::Anthropic;
 
let client = Anthropic::from_env()?;
 
let message = client.messages()
    .create_with_builder("claude-3-5-sonnet-latest", 1024)
    .user("What is the capital of France?")
    .system("You are a helpful geography assistant.")
    .temperature(0.3)
    .send()
    .await?;
 
println!("Response: {:?}", message.content);