A2A Authentication

Before writing code

Fetch live docs:

1. Fetch https://a2a-protocol.org/latest/specification/ for the authentication and security section
2. Web-search site:github.com a2aproject A2A authentication security schemes for auth scheme details
3. Web-search site:github.com a2aproject a2a-samples authentication for auth implementation examples
4. Fetch SDK docs for authentication middleware and client credential handling

Conceptual Architecture

Why Authentication Matters

In multi-agent systems, agents must verify each other's identity and authorize access:

• Server agents need to know who's calling them and whether they're authorized
• Client agents need to present valid credentials to access server agents
• Agent Cards declare what authentication is required upfront