The developer portal is the front door, ownership registry, and golden-path launcher that makes everything else discoverable. Backstage established the pattern; the question is whether to operate it or use a commercial alternative.
Visa's Trusted Agent Protocol (TAP) is an open framework that enables merchants to distinguish legitimate AI shopping agents from bots, verify agent authorization to transact on behalf of a user, and process payments securely using delegated credentials.
AP2 is Google's open protocol for secure, verifiable payment authorization between AI agents, merchants, and payment providers. It introduces cryptographically-signed Mandates as tamper-proof proof of user intent.
UCP is Google's open standard for agentic commerce, covering the full lifecycle from product discovery and comparison through checkout and post-purchase. Backed by a coalition of 20+ partners including Shopify, Walmart, Target, Visa, Mastercard, and Stripe.
ACP is an open standard co-developed by OpenAI and Stripe that defines how AI agents, buyers, and merchants interact to complete purchases programmatically. It powers ChatGPT's Instant Checkout and is the first production-scale agent commerce protocol.
AGNTCY is an open-source infrastructure project under the Linux Foundation that defines how AI agents are described, discovered, connected, and observed across frameworks and vendors.
An open, event-based protocol that standardizes real-time communication between AI agent backends and user-facing frontends. AG-UI fills the third side of the agentic protocol triangle: MCP handles agent-tool, A2A handles agent-agent, AG-UI handles agent-user.
An open-source protocol for agent identity, discovery, and communication across the open internet. ANP tackles the problem that other protocols assume away: how do agents that have never met find each other, verify identity, and negotiate how to communicate?
IBM's open protocol for agent-to-agent communication -- a REST-native, developer-friendly standard for discovering, invoking, and orchestrating AI agents across frameworks.
Google's open protocol for agent-to-agent communication — enabling AI agents built on different frameworks and by different vendors to discover each other, negotiate capabilities, and collaborate on tasks.