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Agent2Agent Protocol (A2A) favicon

Agent2Agent Protocol (A2A)

EcosystemVerified

Google's open protocol for agent-to-agent communication, used alongside UCP for multi-agent commerce orchestration.

The Agent2Agent Protocol (A2A) is an open protocol developed by Google for enabling communication and coordination between AI agents. In UCP commerce flows, A2A handles agent discovery and communication: a user-facing agent can discover a specialized shopping agent via A2A, which then uses UCP to interact with merchants. The official UCP A2A sample demonstrates this combination, using A2A for agent discovery and UCP for merchant checkout.

Why This Matters for UCP

A2A provides the agent discovery and communication layer that enables multi-agent UCP commerce orchestration, allowing specialized shopping agents to be found and coordinated by user-facing AI assistants.

UCP Endpoint

Ecosystem — Endpoint not yet publicly available

Integration Example

// A2A enables agent discovery for UCP commerce:
// 1. User agent discovers a shopping agent via A2A discovery
// 2. Shopping agent authenticates via A2A handshake
// 3. Shopping agent uses UCP to interact with merchant endpoints
// See: github.com/Universal-Commerce-Protocol/samples/tree/main/a2a

UCP Status

Ecosystem

Tags

protocolgoogleagent-communicationopen-sourceorchestration

Pricing

free

Added 2026-03-21
Verified2026-03-21
SourceOpen Source

Reviews

★★★★★4.7 (3 reviews)

These are illustrative examples to show what reviews will look like. Submit your own experience below.

ML

M. Lee

Backend Developer · Mar 3, 2026

★★★★

Works well for our use case. The documentation is accurate and the implementation matches what the spec describes.

RK

R. Kapoor

Platform Engineer · Jan 15, 2026

★★★★★

Integrated in an afternoon. Solid implementation with no unexpected edge cases in production.

JS

J. Santos

Senior Engineer · Feb 28, 2026

★★★★★

Integration was straightforward. The UCP endpoint discovery works as documented and checkout completes in under 2 seconds.

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