a2a-rs-v0.3.0

Fixed

• allow clippy::result_large_err in request processor

Other

• fmt,clippy
• Fix clippy warnings and failing tests
• migrate to Connect-Rust, refactor project structure, update protobuf specs, and clean up temporary scripts
• docs

Changed

• Demoted the ⚠️ No WebSocket subscribers found for task log in
  InMemoryTaskStorage::broadcast_status_update from WARN to DEBUG. The
  no-subscriber case is the steady state for message/send (non-streaming)
  flows and was previously flooding logs on every status broadcast.
  a2a-rs/src/adapter/storage/task_storage.rs:189.

Added - v1.0.0 Compliance

New API Methods

• tasks/list - List tasks with comprehensive filtering and pagination
  • Filter by context_id, status, last_updated_after, and metadata
  • Offset-based pagination with page tokens
  • Configurable history length and artifact inclusion per request
  • Returns ListTasksResult with tasks, total_size, page_size, and next_page_token
• tasks/pushNotificationConfig/list - List all push notification configs for a task
• tasks/pushNotificationConfig/delete - Delete a specific push notification config
• agent/getAuthenticatedExtendedCard - Get extended agent card for authenticated clients

Core Type Enhancements

• Added TransportProtocol enum with JSONRPC, GRPC, and HTTP+JSON variants
• Added AgentInterface type for additional transport protocol interfaces
• Added AgentExtension type for protocol extension framework
  • URI-based extension identification
  • Optional description and required flags
  • Arbitrary parameters via JSON object
• Added extensions field to Message and Artifact types
• Added extensions field to AgentCapabilities

Agent Card Updates

• Added protocol_version field (defaults to "0.3.0")
• Added preferred_transport field (defaults to "JSONRPC")
• Added additional_interfaces field for multi-transport support
• Added icon_url field for agent branding
• Changed signature to signatures (now supports multiple signatures)

Push Notification Enhancements

• Added id field to PushNotificationConfig for unique identification
• Added GetTaskPushNotificationConfigParams for retrieving specific configs
• Added ListTaskPushNotificationConfigParams for listing all configs
• Added DeleteTaskPushNotificationConfigParams for config deletion
• Updated storage implementations with full CRUD operations for push notification configs

Task Management

• Added ListTasksParams with comprehensive filtering options:
  • context_id: Filter by context
  • status: Filter by task state
  • page_size: Control pagination (1-100, default 50)
  • page_token: Offset-based pagination
  • history_length: Control message history depth
  • include_artifacts: Toggle artifact inclusion
  • last_updated_after: Filter by timestamp (ms since epoch)
  • metadata: Filter by metadata fields
• Added ListTasksResult with pagination metadata
• Added list_tasks_v3 to AsyncTaskManager trait
• Added push notification config management methods to AsyncTaskManager:
  • get_push_notification_config
  • list_push_notification_configs
  • delete_push_notification_config

Protocol Migration & ConnectRPC

• Completely migrated from legacy JSON-RPC and WebSocket transport to ConnectRPC (gRPC-compatible) over HTTP.
• Replaced manual JSON-RPC routing with connectrpc-build and prost-generated models based on the official A2A v1.0.0 protocol buffers.
• Deleted legacy WebSocket transport infrastructure across the workspace.
• Updated a2a-client to utilize connectrpc stubs for client-server communication.
• Built and verified a resilient in-process dispatch architecture for MCP standard I/O.

Storage Layer

• Implemented all v1.0.0 methods in InMemoryTaskStorage:
  • Full filtering support for task listing
  • Timestamp-based filtering
  • Metadata filtering
  • Push notification config CRUD operations
• All new trait methods have default implementations returning UnsupportedOperation error
• Proper sorting of tasks by timestamp (most recent first)
• Efficient pagination with configurable page sizes

Error Handling

• Added AuthenticatedExtendedCardNotConfigured error variant
• Moved DATABASE_ERROR code from -32007 to -32100 to avoid conflict with spec

Changed - Breaking Changes

Agent Card

• BREAKING: signature field renamed to signatures and changed to Option<Vec<AgentCardSignature>>
  • Migration: Wrap single signature in a Vec: signature: Some(sig) → signatures: Some(vec![sig])
• BREAKING: Added required protocol_version field (has default: "0.3.0")
• BREAKING: Added required preferred_transport field (has default: "JSONRPC")
• New optional fields: additional_interfaces, icon_url

Message and Artifact

• BREAKING: Added extensions field (optional, defaults to None)
  • Migration: Add extensions: None to all struct initializations

AgentCapabilities

• BREAKING: Added extensions field (optional, defaults to None)
  • Migration: Add extensions: None to all struct initializations

PushNotificationConfig

• BREAKING: Added id field (optional, used for multi-config support)
  • Migration: Add id: None to existing configs

MessageSendConfiguration

• BREAKING: accepted_output_modes is now optional (was required)
  • Migration: Wrap existing values in Some(): vec![...] → Some(vec![...])

Error Codes

• BREAKING: DATABASE_ERROR moved from -32007 to -32100
• New error code: -32007 now used for AUTHENTICATED_EXTENDED_CARD_NOT_CONFIGURED

Migration Guide

Updating Agent Card Initializations

// Before (v0.2.x)
let card = AgentCard {
    signature: Some(my_signature),
    // ... other fields
};

// After (v1.0.0)
let card = AgentCard {
    protocol_version: "0.3.0".to_string(),  // NEW - required
    preferred_transport: "JSONRPC".to_string(),  // NEW - required
    additional_interfaces: None,  // NEW - optional
    icon_url: None,  // NEW - optional
    signatures: Some(vec![my_signature]),  // CHANGED - now plural, wrapped in Vec
    // ... other fields
};

Updating Message and Artifact Initializations

// Before (v0.2.x)
let message = Message {
    message_id: "msg-1".to_string(),
    // ... other fields
};

// After (v1.0.0)
let message = Message {
    message_id: "msg-1".to_string(),
    extensions: None,  // NEW - add this field
    // ... other fields
};

// Same for Artifact
let artifact = Artifact {
    artifact_id: "art-1".to_string(),
    extensions: None,  // NEW - add this field
    // ... other fields
};

Updating Capabilities

// Before (v0.2.x)
let caps = AgentCapabilities {
    streaming: true,
    push_notifications: false,
    state_transition_history: true,
};

// After (v1.0.0)
let caps = AgentCapabilities {
    streaming: true,
    push_notifications: false,
    state_transition_history: true,
    extensions: None,  // NEW - add this field
};

Updating Push Notification Configs

// Before (v0.2.x)
let config = PushNotificationConfig {
    url: "https://example.com/webhook".to_string(),
    token: Some("token".to_string()),
    authentication: None,
};

// After (v1.0.0)
let config = PushNotificationConfig {
    id: None,  // NEW - for multi-config support
    url: "https://example.com/webhook".to_string(),
    token: Some("token".to_string()),
    authentication: None,
};

Using New Task Listing API

use a2a_rs::domain::{ListTasksParams, TaskState};

// List tasks with filtering and pagination
let params = ListTasksParams {
    context_id: Some("ctx-123".to_string()),
    status: Some(TaskState::Working),
    page_size: Some(25),
    page_token: None,  // Start at beginning
    history_length: Some(10),
    include_artifacts: Some(true),
    last_updated_after: None,
    metadata: None,
};

let result = task_manager.list_tasks_v3(&params).await?;
println!("Found {} tasks, showing {}", result.total_size, result.tasks.len());

// Get next page if available
if !result.next_page_token.is_empty() {
    let next_params = ListTasksParams {
        page_token: Some(result.next_page_token),
        ..params
    };
    let next_result = task_manager.list_tasks_v3(&next_params).await?;
}

Managing Push Notification Configs

use a2a_rs::domain::{
    GetTaskPushNotificationConfigParams,
    ListTaskPushNotificationConfigParams,
    DeleteTaskPushNotificationConfigParams,
};

// List all configs for a task
let list_params = ListTaskPushNotificationConfigParams {
    id: "task-123".to_string(),
    metadata: None,
};
let configs = task_manager.list_push_notification_configs(&list_params).await?;

// Get a specific config
let get_params = GetTaskPushNotificationConfigParams {
    id: "task-123".to_string(),
    push_notification_config_id: Some("config-1".to_string()),
    metadata: None,
};
let config = task_manager.get_push_notification_config(&get_params).await?;

// Delete a config
let delete_params = DeleteTaskPushNotificationConfigParams {
    id: "task-123".to_string(),
    push_notification_config_id: "config-1".to_string(),
    metadata: None,
};
task_manager.delete_push_notification_config(&delete_params).await?;

Notes

• All new trait methods have default implementations that return UnsupportedOperation error
• Existing code will continue to work after adding required fields to struct initializations
• The InMemoryTaskStorage implementation supports all new features
• SQLx storage implementations need to be updated to support multi-config push notifications