Streaming

TraitClaw provides first-class streaming via async Stream with strongly-typed events.

Basic Streaming

use futures::StreamExt;

let mut stream = agent.stream("Tell me about Rust's type system");

while let Some(Ok(event)) = stream.next().await {
    match event {
        StreamEvent::TextDelta(text) => print!("{text}"),
        StreamEvent::Done(output) => {
            println!("\n\nTokens used: {}", output.usage().total_tokens);
        }
        _ => {}
    }
}

Stream Events

Event	Description
TextDelta(String)	New text chunk from the LLM
ToolStart { name, id }	Agent is about to call a tool
ToolEnd { id, result }	Tool execution completed
ThoughtStep(ThoughtStep)	Strategy reasoning step (ReAct/CoT)
Done(AgentOutput)	Stream complete with final output
Error(Error)	An error occurred

With Tool Calling

When the agent uses tools during streaming, you get full visibility:

while let Some(Ok(event)) = stream.next().await {
    match event {
        StreamEvent::TextDelta(text) => print!("{text}"),
        StreamEvent::ToolStart { name, .. } => {
            println!("\n🔧 Calling tool: {name}...");
        }
        StreamEvent::ToolEnd { result, .. } => {
            println!("   Result: {}", result.content);
        }
        StreamEvent::ThoughtStep(step) => {
            println!("💭 {}: {}", step.step_type, step.content);
        }
        StreamEvent::Done(_) => println!("\n✅ Complete"),
        _ => {}
    }
}