a2a-reference-ts · packages

Pluggable authentication and authorization strategies for A2A agents, providing `NoneStrategy`, `ApiKeyStrategy`, `JwtStrategy`, and `OAuth2Strategy` classes plus a `extractScopes` utility function. Designed for use with the A2A agent framework.

A type-safe A2A client SDK that provides a class (`A2AClient`) for task submission, agent discovery, and SSE streaming against A2A-compatible servers. It handles agent card caching, retries with exponential backoff, and supports both synchronous task management and async event streaming via `sendSubscribe`.

Zod schemas, TypeScript types, error classes, and a signature verification function for the A2A (Agent-to-Agent) protocol, providing canonical validation and parsing for task lifecycle messages, agent cards, and security schemes.

A bidirectional protocol adapter that exposes MCP tools as A2A skills via `McpToolAdapter` (producing an enriched Agent Card), and wraps an A2A agent as an MCP server via `A2aAsMcpServer` (starting a stdio or SSE transport).

Pino-based structured logging with correlation IDs and OpenTelemetry abstractions (tracers, meters, spans) for A2A agents, providing `createLogger`, `withCorrelationId`, `getTracer`, `getMeter`, and `withTaskSpan` functions with no-op defaults that can be replaced by a custom `TelemetryProvider`.

Provides in-memory, filesystem, Redis, and Postgres implementations of a `TaskStore` interface for persisting A2A (Agent-to-Agent) tasks, each exposed as a class constructor.

A server framework that implements the A2A (Agent-to-Agent) protocol, providing Express 5 and Hono adapters that expose JSON-RPC 2.0 endpoints, SSE streaming, health checks, rate limiting, and push notifications for agent communication.