A2A over ZAP

Status — spec-only, January 2026. The wire schema is published; the Go runtime hasn't shipped. Use the schema with any SDK for codegen of the message types. The transport / dispatch layer is being designed in zap-proto/papers.

zap-proto/a2a is the ZAP-native carrier for Google's Agent-to-Agent (A2A) protocol — agent cards advertise capabilities, tasks are issued and tracked, artifacts flow between agents.

Why on ZAP

Running A2A on ZAP buys you the same authentication / authorization / observability story ZAP gives any higher-level protocol:

• Trustworthy agent cards — the publishing agent signs its own card under its PQ identity. Consumers verify without a separate PKI.
• Provable task lineage — every state transition is signed. Disputes are settled by signature, not by audit-log trust.
• Streaming-native artifacts — large artifacts are zero-copy buffers, not gRPC-serialized blobs.

Schema

Published at zap-proto/a2a/schema/zap_a2a.zap. The schema covers:

• AgentCard — name, description, skills, capabilities, identity
• Task — id, skill, inputs, state machine
• Artifact — name, content-type, payload
• Update — task state transitions, signed by the executing agent
• Standard error variants

Generate types via the per-language codegen (SDKs), even though the runtime isn't shipped — the encoded bytes are stable.

Roadmap

Track progress on zap-proto/a2a.

Related

• Google A2A specification — upstream spec
• Native ZAP RPC — the underlying RPC layer A2A maps to
• ACP over ZAP — FIPA-style alternative for structured dialog
• RNS — for keying agent discovery to identity rather than DNS