PRACTICAL A2A GUIDE
A2A, or Agent2Agent, gives AI agents a structured way to discover one another, understand their capabilities and exchange tasks. Website readiness starts with a public Agent Card, clear interfaces and secure authentication.
SHORT ANSWER
A2A is not a chatbot or another SEO file. It is a shared contract for describing what an agent can do and exchanging tasks with it safely.
01
A normal web interface is designed for people. An A2A interface tells machines which agent is available, what it can do, which protocol it uses and how to connect. It adds an agent collaboration layer without replacing the website.
02
An Agent Card is commonly published at a well-known URL. It describes the agent, skills, interfaces and security schemes. A file alone is not enough: its URLs and advertised capabilities must work.
03
A skill might find a product, check an order or analyse a document. The interface defines the protocol, version and secure HTTPS URL, allowing another agent to choose the right capability without guessing.
04
A public Agent Card does not make every action public. OAuth or another declared scheme should separate read, write and side-effecting access. Purchases, bookings and data changes require clear authority and often human approval.
05
A2A coordinates tasks between agents. MCP connects a model to tools and data. llms.txt and Markdown may make content easier to retrieve, but they do not create an A2A agent or a secure action flow.
06
A useful audit checks the Agent Card shape, interfaces, skills, security metadata and a side-effect-free response. Missing ACP, UCP, MCP or x402 is not automatically a violation when a site does not advertise it.
FAQ
No. A2A is useful when another agent must exchange structured tasks with your system.
No. It does not replace an Agent Card, A2A interface, authentication or task lifecycle.
Yes. It describes capabilities, while protected actions and data still require appropriate authorization.
Check discovery, Agent Card shape, interfaces, skills, authentication and safe error handling.