Ecosystem, indexed.

The largest live directory of A2A agents — official Google samples, community implementations, multi-language guides, browsable with zero setup.

Global public registry for the A2A protocol — register in under 5 minutes, machine-facing discovery via POST /a2a/discover, routing without hardcoded URLs.

Strongly typed Python A2A library with Pydantic v2, dataclasses, and robust serialization support.

Modular .NET A2A SDK — Core, Client, Server, HTTP + gRPC + JSON-RPC, Redis persistence, Quartz scheduling: assemble only what you need.

Full Java A2A stack - separate Spring Boot client/server starters, BOM, Reactor SSE streaming, spec-faithful A2A 1.0 support, and Maven Central distribution.

Full-stack A2A framework — Python backend + Node.js frontend included, multi-agent coordination with host agent, MCP tools via JSON config, RAG and DeepSearch agents ready to deploy.

Minimal Python A2A implementation covering client and server basics, task lifecycle, streaming, and push updates.

979 stars — the most complete Python A2A framework: workflow engine, AI router, Agent Flow UI drag-and-drop, native LangChain, MCP v2.0 with GitHub/Browserbase/Filesystem providers, full CLI.