Crate tower_a2a 

Tower A2A

A Tower-based implementation of the Agent2Agent (A2A) protocol.

This library provides a composable, transport-agnostic implementation of the A2A protocol using Tower’s Service and Layer abstractions. It supports multiple transport protocols (HTTP, gRPC, WebSocket) through a unified interface.

Features

• Transport Agnostic: Works with HTTP, gRPC, WebSocket, or custom transports
• Composable Middleware: Auth, retry, timeout, validation as Tower layers
• Type Safe: Compile-time guarantees for protocol operations
• Async: Built on tokio for high performance

Example

use tower_a2a::prelude::*;
use std::time::Duration;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let url = "https://agent.example.com".parse().unwrap();
    let mut client = A2AClientBuilder::new_http(url)
        .with_bearer_auth("token123".to_string())
        .with_timeout(Duration::from_secs(30))
        .build()?;

    let agent_card = client.discover().await?;
    println!("Connected to: {}", agent_card.name);

    Ok(())
}

Modules

client

High-level client API for A2A protocol

codec

Serialization codecs for different protocol bindings

layer

Tower Layer implementations for A2A protocol

prelude

Prelude module for convenient imports

protocol

Core A2A protocol types and definitions

service

Tower Service implementations

transport

Transport abstraction layer for A2A protocol