A2A Messages and Parts

Before writing code

Fetch live docs:

1. Fetch https://a2a-protocol.org/latest/specification/ for the Message and Part schemas
2. Web-search site:github.com a2aproject A2A message parts TextPart FilePart DataPart for schema details
3. Web-search site:github.com a2aproject a2a-samples message for message construction examples
4. Fetch SDK docs for message builder classes and part types

Conceptual Architecture

What Messages Are

Messages are the communication units between agents in A2A. Each message belongs to a task and contains one or more Parts that carry the actual content. Messages have roles indicating direction.

Message Structure