Module server 

Server framework for implementing A2A agents.

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.

executor_helpers

Ergonomic helpers for implementing AgentExecutor.

handler

Core request handler — protocol logic layer.

interceptor

Server-side interceptor chain.

metrics

Metrics hooks for observing handler activity.

otel

OpenTelemetry integration for the A2A server.

push

Push notification configuration storage and delivery.

rate_limit

Token-bucket rate limiter as a ServerInterceptor.

request_context

Request context passed to the AgentExecutor.

serve

Server startup helpers.

store

Task storage backend.

streaming

Streaming infrastructure for SSE responses and event queues.

tenant_config

Per-tenant configuration for multi-tenant A2A servers.

tenant_resolver

Tenant resolution for multi-tenant A2A servers.

Macros

agent_executor

Generates an AgentExecutor implementation from a closure-like syntax.

Structs

A2aRouter

Builder for an Axum Router that serves all A2A v1.0 protocol methods.

BearerTokenTenantResolver

Extracts a tenant ID from the Authorization: Bearer <token> header.

CallContext

Metadata about the current server-side method call.

ConnectionPoolStats

Statistics about the HTTP connection pool.

CorsConfig

CORS configuration for A2A dispatchers.

DispatchConfig

Configuration for dispatch-layer limits shared by both JSON-RPC and REST dispatchers.

DynamicAgentCardHandler

Serves a dynamically generated AgentCard as a JSON HTTP response.

EventEmitter

Ergonomic helper for emitting status and artifact events from an executor.

EventQueueManager

Manages event queues for active tasks.

GrpcConfig

Configuration for the gRPC dispatcher.

GrpcDispatcher

gRPC dispatcher that routes A2A requests to a RequestHandler.

HandlerLimits

Configurable limits for the request handler.

HeaderTenantResolver

Extracts a tenant ID from a configurable HTTP header.

HotReloadAgentCardHandler

An agent card handler that supports hot-reloading.

HttpPushSender

HTTP-based PushSender using hyper.

InMemoryPushConfigStore

In-memory PushConfigStore backed by a HashMap.

InMemoryQueueReader

In-memory EventQueueReader backed by a broadcast channel receiver.

InMemoryQueueWriter

In-memory EventQueueWriter backed by a broadcast channel sender.

InMemoryTaskStore

In-memory TaskStore backed by a BTreeMap under a RwLock.

JsonRpcDispatcher

JSON-RPC 2.0 request dispatcher.

Migration

A single schema migration.

MigrationRunner

Runs schema migrations against a SQLite database.

OtelMetrics

A Metrics implementation backed by OpenTelemetry instruments.

PathSegmentTenantResolver

Extracts a tenant ID from a URL path segment by index.

PerTenantConfig

Per-tenant configuration for timeouts, capacity limits, and executor selection.

PgMigration

A single schema migration.

PgMigrationRunner

Runs schema migrations against a PostgreSQL database.

PostgresPushConfigStore

PostgreSQL-backed PushConfigStore.

PostgresTaskStore

PostgreSQL-backed TaskStore.

PushRetryPolicy

Retry policy for push notification delivery.

RateLimitConfig

Configuration for RateLimitInterceptor.

RateLimitInterceptor

A fixed-window rate limiting ServerInterceptor.

RequestContext

Context for a single agent execution request.

RequestHandler

The core protocol logic handler.

RequestHandlerBuilder

Fluent builder for RequestHandler.

RestDispatcher

REST HTTP request dispatcher.

ServerInterceptorChain

An ordered chain of ServerInterceptor instances.

SqlitePushConfigStore

SQLite-backed PushConfigStore.

SqliteTaskStore

SQLite-backed TaskStore.

StaticAgentCardHandler

Serves a pre-serialized AgentCard as a JSON HTTP response with caching.

TaskStoreConfig

Configuration for InMemoryTaskStore.

TenantAwareInMemoryPushConfigStore

Tenant-isolated in-memory PushConfigStore.

TenantAwareInMemoryTaskStore

Tenant-isolated in-memory TaskStore.

TenantAwarePostgresPushConfigStore

Tenant-scoped PostgreSQL-backed PushConfigStore.

TenantAwarePostgresTaskStore

Tenant-scoped PostgreSQL-backed TaskStore.

TenantAwareSqlitePushConfigStore

Tenant-scoped SQLite-backed PushConfigStore.

TenantAwareSqliteTaskStore

Tenant-scoped SQLite-backed TaskStore.

TenantContext

Thread-safe tenant context for scoping store operations.

TenantLimits

Resource limits and configuration for a single tenant.

TenantStoreConfig

Configuration for TenantAwareInMemoryTaskStore.

WebSocketDispatcher

WebSocket-based A2A dispatcher.

Enums

SendMessageResult

Result of RequestHandler::on_send_message.

ServerError

Server framework error type.

Constants

CORS_ALLOW_ALL

CORS Access-Control-Allow-Origin header value for public agent cards.

Traits

AgentCardProducer

Trait for producing an AgentCard dynamically.

AgentExecutor

Trait for implementing A2A agent execution logic.

Dispatcher

Trait for types that can dispatch HTTP requests to an A2A handler.

EventQueueReader

Trait for reading streaming events.

EventQueueWriter

Trait for writing streaming events.

Metrics

Trait for receiving metrics callbacks from the handler.

PushConfigStore

Trait for storing push notification configurations.

PushSender

Trait for delivering push notifications to client webhooks.

ServerInterceptor

A server-side interceptor for request processing.

TaskStore

Trait for persisting and retrieving Task objects.

TenantResolver

Trait for extracting a tenant identifier from incoming requests.

Functions

boxed_future

Wraps an async expression into Pin<Box<dyn Future<Output = T> + Send + 'a>>.

serve

Starts an HTTP server that dispatches requests using the given dispatcher.

serve_with_addr

Starts an HTTP server and returns the bound SocketAddr.

Type Aliases

ServerResult

Convenience type alias: Result<T, ServerError>.