Back to Directory
Agent Payments Protocol (AP2) favicon

Agent Payments Protocol (AP2)

EcosystemVerified

Google's secure payment authorization protocol for AI agents, providing cryptographic consent for UCP transactions.

The Agent Payments Protocol (AP2) is a secure payment protocol developed in the Google agentic commerce ecosystem. AP2 mandates provide cryptographic proof of user authorization when an AI agent initiates a purchase, ensuring that payment processors and merchants can verify the intent and scope of agent-initiated transactions. AP2 works alongside UCP: UCP handles the commerce flow, while AP2 secures the payment authorization chain.

Why This Matters for UCP

AP2 provides the secure payment authorization layer for UCP transactions, enabling merchants and payment processors to cryptographically verify that an AI agent is acting within its authorized scope.

UCP Capabilities

payment token exchange

UCP Endpoint

Ecosystem — Endpoint not yet publicly available

Integration Example

// AP2 secures UCP payment authorization:
// 1. User grants agent purchase authorization via AP2 mandate
// 2. Agent includes AP2 proof in UCP checkout session
// 3. Merchant verifies AP2 proof before fulfilling order
// This creates a tamper-resistant authorization chain.

UCP Status

Ecosystem

Tags

protocolgooglepaymentssecuritycryptographicauthorization

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.

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.

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.

3 other tools in Related Protocols

Is this your tool? Claim this listing

Related Related Protocols

Model Context Protocol (MCP) favicon

Model Context Protocol (MCP)

Related Protocols

Ecosystem

Anthropic's open protocol for connecting AI models to external data sources and tools, complementary to UCP.

protocolanthropicopen-standard
UnverifiedAgent-Ready: 20%
3.6implementation(26 signals)
Open Sourcefree
Agent2Agent Protocol (A2A) favicon

Agent2Agent Protocol (A2A)

Related Protocols

Ecosystem

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

protocolgoogleagent-communication
UnverifiedAgent-Ready: 20%
3.2implementation(35 signals)
Open Sourcefree
Agentic Commerce Protocol (ACP) favicon

Agentic Commerce Protocol (ACP)

Related Protocols

Ecosystem

Open standard for AI-native commerce, complementary to UCP, with a focus on high-level commerce action orchestration.

protocolopen-standardenterprise
UnverifiedAgent-Ready: 40%
4.2implementation(18 signals)
free