// Follow protocols & specs
a2a-jsv1.3.0
Official JavaScript SDK for the Agent2Agent (A2A) Protocol
Open source Maintained For agents
IN ONE PARAGRAPH
a2a-js is official JavaScript SDK for the Agent2Agent (A2A) Protocol.
Good for: Developers who want their agent (Claude Code, Codex, Cursor…) to follow protocols & specs.
01How to start
- 1Read the official README for requirements and permissions.
- 2Install it from the official package registry:
npm install @mailmodo/a2a - 3Tell your agent the command exists (e.g. in AGENTS.md / CLAUDE.md) so it knows when to call it.
02Alternatives & comparison
Compare side by side → A2A Agent2Agent (A2A) is an open protocol enabling communication and interoperability between opaque agentic applications. ★ 26k agents.md AGENTS.md — a simple, open format for guiding coding agents ★ 25k modelcontextprotocol Specification and documentation for the Model Context Protocol ★ 9.5k agent-client-protocol A protocol for connecting any editor to any agent ★ 4.4k llms-txt The /llms.txt file, helping language models use your website ★ 2.7k
03Related
- ›Hugging Face AI Agents Course · Hugging FaceMultilingual (incl. EN/ZH)
- ›huggingface/agents-course · Hugging FaceEnglish
- ›AI Agents for Beginners · MicrosoftMultilingual (incl. EN/ZH)
- ›Building effective agents · AnthropicEnglish
- ›OpenAI: A practical guide to building agents · OpenAIEnglish
- All tutorials →
Versions, why it is listed, for AI to read
Recent releases
- v1.3.0 2026-09-29
- v1.2.1 2026-09-24
- v1.2.0 2026-09-18
- v1.1.0 2026-08-26
- v0.3.14+itk 2026-08-13
For AI agents
- Interfaces：SDK
- Machine-readable record：/api/v1/software/a2a-js.json · llms.txt
- Added 2026-10-10 · updated 2026-10-22