Crate a2a_protocol_server 

A2A protocol v1.0 — server framework.

Provides RequestHandler and AgentExecutor for implementing A2A agents over HTTP/1.1 and HTTP/2 using hyper 1.x.

Quick start

1. Implement AgentExecutor with your agent logic.
2. Build a RequestHandler via RequestHandlerBuilder.
3. Wire JsonRpcDispatcher or RestDispatcher into your hyper server.

Module overview

Module	Contents
error	ServerError, ServerResult
executor	AgentExecutor trait
handler	RequestHandler, SendMessageResult
builder	RequestHandlerBuilder
store	TaskStore, InMemoryTaskStore
streaming	Event queues, SSE response builder
push	Push config store, push sender
agent_card	Static/dynamic agent card handlers
dispatch	JsonRpcDispatcher, RestDispatcher
interceptor	ServerInterceptor, ServerInterceptorChain
request_context	RequestContext
call_context	CallContext

Transport limitations

The A2A specification lists gRPC as an optional transport binding. This implementation currently supports HTTP + SSE only; gRPC transport is not yet implemented.

Rate limiting

This library does not perform request rate limiting. Deployments that require rate limiting should handle it in a reverse proxy (e.g. nginx, Envoy) or a middleware layer in front of the A2A handler.

Re-exports

pub use agent_card::AgentCardProducer;

pub use agent_card::DynamicAgentCardHandler;

pub use agent_card::StaticAgentCardHandler;

pub use agent_card::CORS_ALLOW_ALL;

pub use builder::RequestHandlerBuilder;

pub use call_context::CallContext;

pub use dispatch::CorsConfig;

pub use dispatch::JsonRpcDispatcher;

pub use dispatch::RestDispatcher;

pub use error::ServerError;

pub use error::ServerResult;

pub use executor::AgentExecutor;

pub use handler::RequestHandler;

pub use handler::SendMessageResult;

pub use interceptor::ServerInterceptor;

pub use interceptor::ServerInterceptorChain;

pub use push::HttpPushSender;

pub use push::InMemoryPushConfigStore;

pub use push::PushConfigStore;

pub use push::PushSender;

pub use request_context::RequestContext;

pub use store::InMemoryTaskStore;

pub use store::TaskStore;

pub use store::TaskStoreConfig;

pub use streaming::EventQueueManager;

pub use streaming::EventQueueReader;

pub use streaming::EventQueueWriter;

pub use streaming::InMemoryQueueReader;

pub use streaming::InMemoryQueueWriter;

Modules

agent_card

Agent card HTTP handlers (static, dynamic, and caching utilities).

builder

Builder for RequestHandler.

call_context

Call context for server-side interceptors.

dispatch

HTTP dispatch layer — JSON-RPC and REST routing.

error

Server-specific error types.

executor

Agent executor trait.

handler

Core request handler — protocol logic layer.

interceptor

Server-side interceptor chain.

metrics

Metrics hooks for observing handler activity.

push

Push notification configuration storage and delivery.

request_context

Request context passed to the AgentExecutor.

store

Task storage backend.

streaming

Streaming infrastructure for SSE responses and event queues.