{
  "source": "Agentic Commerce Atlas",
  "url": "https://agenticcommerceatlas.com",
  "license": "CC BY 4.0: quote or reuse with attribution to Agentic Commerce Atlas.",
  "updated": "2026-06-29",
  "protocols": [
    {
      "id": "acp",
      "name": "ACP",
      "fullName": "Agentic Commerce Protocol",
      "layer": "commerce-semantics",
      "maintainer": "OpenAI, Stripe, Meta",
      "license": "Apache-2.0",
      "status": "beta",
      "announced": "2025-09-29",
      "specUrl": "https://github.com/agentic-commerce-protocol/agentic-commerce-protocol",
      "atlasUrl": "https://agenticcommerceatlas.com/learn/acp-explained",
      "summary": "Open standard for agent-to-merchant checkout. Powered the original ChatGPT Instant Checkout. Payment flows via a Shared Payment Token scoped to one merchant and cart total."
    },
    {
      "id": "ucp",
      "name": "UCP",
      "fullName": "Universal Commerce Protocol",
      "layer": "commerce-semantics",
      "maintainer": "Google and the UCP Tech Council (Shopify, Etsy, Target, Wayfair, plus Amazon, Meta, Microsoft, Salesforce, Stripe from April 2026)",
      "license": "Apache-2.0",
      "status": "launched",
      "announced": "2026-01-11",
      "specUrl": "https://ucp.dev/",
      "atlasUrl": "https://agenticcommerceatlas.com/learn/ucp-explained",
      "summary": "Google's standard covering the full shopping journey from discovery through checkout to post-purchase. The main rival to ACP at the commerce layer; pairs with AP2 for payments. In April 2026 Amazon, Meta, Microsoft, Salesforce, and Stripe joined the UCP Tech Council, doubling it to ten members. At Google Marketing Live in May 2026, Google extended UCP with named-brand Universal Cart and into new verticals, hotel booking and food delivery."
    },
    {
      "id": "ap2",
      "name": "AP2",
      "fullName": "Agent Payments Protocol",
      "layer": "payment-authorization",
      "maintainer": "FIDO Alliance (originated at Google)",
      "license": "Apache-2.0",
      "status": "pre-production",
      "announced": "2025-09-16",
      "specUrl": "https://ap2-protocol.org/",
      "atlasUrl": "https://agenticcommerceatlas.com/learn/ap2-explained",
      "summary": "Payment-authorization and trust standard using signed mandates as verifiable credentials. Donated to the FIDO Alliance in April 2026. Visa and Stripe are notably absent from launch partners."
    },
    {
      "id": "mcp",
      "name": "MCP",
      "fullName": "Model Context Protocol",
      "layer": "discovery",
      "maintainer": "Anthropic (donated to a foundation, Dec 2025)",
      "license": "open source",
      "status": "widely adopted",
      "announced": "2024-11",
      "specUrl": "https://modelcontextprotocol.io/",
      "atlasUrl": "https://agenticcommerceatlas.com/learn/mcp-explained",
      "summary": "General standard for connecting AI agents to tools and data. Not a commerce protocol; in commerce it acts as the discovery layer, and ACP and UCP can use it as a transport."
    },
    {
      "id": "a2a",
      "name": "A2A",
      "fullName": "Agent-to-Agent",
      "layer": "agent-coordination",
      "maintainer": "Linux Foundation (originated at Google)",
      "license": "open source",
      "status": "v1.0",
      "specUrl": "https://a2a-protocol.org/",
      "atlasUrl": "https://agenticcommerceatlas.com/learn/a2a-explained",
      "summary": "Standard for how independent agents communicate and delegate tasks. AP2 is built as an extension of A2A."
    },
    {
      "id": "x402",
      "name": "x402",
      "fullName": "x402",
      "layer": "settlement",
      "maintainer": "Coinbase (x402 Foundation, under the Linux Foundation)",
      "license": "open source",
      "status": "live",
      "announced": "2025-05",
      "specUrl": "https://github.com/coinbase/x402",
      "atlasUrl": "https://agenticcommerceatlas.com/learn/x402-explained",
      "summary": "Revives the HTTP 402 status for stablecoin payments between software. Aimed at machine-to-machine and micro-transactions rather than consumer checkout. Aligned with AP2 via an x402 extension."
    },
    {
      "id": "mpp",
      "name": "MPP",
      "fullName": "Machine Payments Protocol",
      "layer": "settlement",
      "maintainer": "Stripe and Tempo",
      "license": "open source",
      "status": "live",
      "announced": "2026-03-18",
      "specUrl": "https://mpp.dev/",
      "atlasUrl": "https://agenticcommerceatlas.com/learn/mpp-explained",
      "summary": "Open standard co-authored by Stripe and Tempo for agents to pay services programmatically. Aimed at machine-to-machine microtransactions and recurring payments; supports stablecoins as well as cards and buy-now-pay-later via Shared Payment Tokens. Sits alongside x402 at the settlement layer."
    }
  ]
}