Question 1

What is an A2A Agent Card?

Accepted Answer

An Agent Card is a JSON document used by the Agent2Agent (A2A) protocol, usually served at /.well-known/agent-card.json, that describes an agent so other agents can discover and call it — its name, description, endpoint URL, capabilities (streaming, push notifications), input/output modes and the skills it offers.

Question 2

Where do I host the agent card?

Accepted Answer

Serve the generated JSON at https://your-domain/.well-known/agent-card.json. Keep the url, skills and capabilities in sync with what your agent actually implements so calling agents don't get rejected.

Question 3

How does A2A relate to MCP?

Accepted Answer

MCP connects an agent to tools and data; A2A connects agents to other agents. Together with an ai-catalog.json manifest, an A2A Agent Card and an MCP Server Card form the well-known discovery set that lets the agentic web find and use what you expose.

A2A Agent Card generator