---
title: "Securing Agentic Commerce"
description: "Agentic commerce is moving from AI-assisted product discovery toward purchases completed by agents, but retail systems often cannot reliably establish the shopper’s identity or spending authority. The post describes four phases—product discovery, checkout functions, delegate-to-buy, and agent-to-agent commerce—and notes standards including UCP, ACP, and AP2. Auth0’s approach combines user authentication, asynchronous authorization, and authentication for MCP, using CIMD-based agent registration, OAuth, and on-behalf-of token exchange to issue temporary, scoped transaction access. It presents third-party shopping agents and retailer-owned agents as two deployment models, with actions tied to an authenticated shopper and recorded for auditability. The proposed identity layer can sit alongside an existing identity provider while supporting emerging protocols and future autonomous purchasing."
---

# Securing Agentic Commerce

[Auth0](https://yomu.fyi/company/auth0) · Bradford Peirce · Aug 31, 2026

**Type:** Explainer

## Summary

Agentic commerce is moving from AI-assisted product discovery toward purchases completed by agents, but retail systems often cannot reliably establish the shopper’s identity or spending authority. The post describes four phases—product discovery, checkout functions, delegate-to-buy, and agent-to-agent commerce—and notes standards including UCP, ACP, and AP2. Auth0’s approach combines user authentication, asynchronous authorization, and authentication for MCP, using CIMD-based agent registration, OAuth, and on-behalf-of token exchange to issue temporary, scoped transaction access. It presents third-party shopping agents and retailer-owned agents as two deployment models, with actions tied to an authenticated shopper and recorded for auditability. The proposed identity layer can sit alongside an existing identity provider while supporting emerging protocols and future autonomous purchasing.

## Context

Retail systems must determine whether an AI action comes from a real, authorized human and whether that person has permission to spend the money. The post frames identity and authorization as prerequisites for retailers seeking to support purchases through third-party or proprietary shopping agents.

## Approach / What changed

The approach adds an agent identity layer alongside an existing identity provider. It uses MCP security, CIMD-based agent registration, OAuth-based shopper verification, and on-behalf-of token exchange to give agents temporary, scoped access tied to an approved transaction or authenticated session.

## Takeaways

- Agentic commerce is described in four phases: product discovery, checkout functions, delegate-to-buy, and agent-to-agent commerce.
- On-behalf-of token exchange prevents an agent from holding a master credential by issuing a temporary, transaction-specific pass after shopper approval.
- Retailers can secure either third-party shopping agents operating through platforms such as ChatGPT and Gemini or proprietary agents embedded in their own sites and apps.

**Tags:** [AI Agents](https://yomu.fyi/topic/ai-agents), [Authentication](https://yomu.fyi/topic/authentication), [MCP](https://yomu.fyi/topic/mcp), [Security](https://yomu.fyi/topic/security)

- Source: [Auth0](https://auth0.com/blog/securing-agentic-commerce)
- Source URL: https://auth0.com/blog/securing-agentic-commerce
- Ingested by Yomu: 2026-08-31T20:00:48.270Z

[Read original post](https://auth0.com/blog/securing-agentic-commerce)