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Message (A2A)

Reviewed 19 July 2026 Canonical definition Part of: MCP & Agent Protocol Terms →

A message in A2A is a single exchange between agents within a task. It carries the content, sender role, and any metadata needed to continue the workflow.

§01 / QUESTIONSterm: Message (A2A)
Questions

Common questions.

What is Message (A2A)?

A message in A2A is a single exchange between agents within a task.

How does Message (A2A) work?

It carries the content, sender role, and any metadata needed to continue the workflow.

Which terms are related to Message (A2A)?

Closely related concepts include Content Modality (A2A), MCP (Model Context Protocol), Model Context Protocol (MCP), MCP Poisoning. Each is defined in the Prefactor glossary.

§02 / RELATEDnext: where this fits
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Where this fits.

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