{
  "schema_version": "protocol.v1",
  "slug": "x402",
  "name": "x402",
  "status": "production-ready",
  "website": "https://www.x402.org/",
  "summary": "HTTP-native payment protocol for programmatic stablecoin payments, API monetization, paid content, and agent-to-service commerce.",
  "categories": [
    "payments",
    "agent-commerce",
    "http",
    "stablecoins"
  ],
  "chains": [
    "base",
    "polygon",
    "arbitrum-one"
  ],
  "best_for": [
    "agentic payments",
    "paid API access",
    "pay-per-request commerce",
    "stablecoin micropayments"
  ],
  "avoid_for": [
    "marketplaces that need built-in dispute resolution, escrow, fulfillment, or inventory management",
    "payments where card rails, fiat settlement, or buyer chargebacks are required"
  ],
  "integration_difficulty": "medium",
  "tags": [
    "x402",
    "http-402",
    "payments",
    "stablecoins",
    "agentic-commerce"
  ],
  "composition": [
    {
      "slug": "erc-8004",
      "role": "agent_identity_and_trust",
      "direction": "supports",
      "relationship": "ERC-8004 can provide agent identity, discovery, reputation, and validation around paid x402 service endpoints.",
      "best_for": [
        "agent marketplaces and paid API access"
      ]
    },
    {
      "slug": "lighthouse-storage",
      "role": "storage",
      "direction": "supports",
      "relationship": "Lighthouse can store agent-readable manifests, paid-content artifacts, receipts, or service metadata referenced by paid endpoints."
    },
    {
      "slug": "goldsky",
      "role": "indexing_and_data",
      "direction": "supports",
      "relationship": "Goldsky can index payment, fulfillment, refund, and feedback events for paid service dashboards."
    }
  ],
  "docs": {
    "url": "https://docs.cdp.coinbase.com/x402/",
    "verified_at": "2026-06-03"
  },
  "sdk": {
    "url": "https://github.com/x402-foundation/x402",
    "verified_at": "2026-06-03"
  },
  "template": {
    "url": "https://docs.cdp.coinbase.com/x402/quickstart-for-sellers",
    "verified_at": "2026-06-03"
  },
  "support": {
    "url": "https://discord.gg/cdp",
    "verified_at": "2026-06-03"
  },
  "grant": {
    "url": null,
    "verified_at": "2026-06-03"
  },
  "capabilities": [
    {
      "name": "HTTP 402 payment flow",
      "status": "production-ready",
      "type": "integration_workflow",
      "best_for": [
        "servers that return payment instructions with HTTP 402",
        "clients and agents that retry with payment headers",
        "paid APIs and digital goods"
      ],
      "known_issues": [
        "x402 covers payment authorization and settlement, not marketplace fulfillment, escrow, returns, or dispute handling."
      ],
      "agent_actions": [
        "generate_payment_required_flow",
        "recommend_agent_payment_stack"
      ]
    },
    {
      "name": "Facilitator verification and settlement",
      "status": "production-ready",
      "type": "production_surface",
      "best_for": [
        "sellers that do not want to run blockchain verification infrastructure",
        "ERC-20 stablecoin settlement",
        "multi-network payment acceptance"
      ],
      "known_issues": [
        "Network, token, facilitator, and transaction-pricing assumptions must be verified before production."
      ],
      "agent_actions": [
        "generate_facilitator_checks",
        "recommend_supported_networks"
      ]
    }
  ],
  "known_issues": [
    {
      "id": "x402-marketplace-scope",
      "title": "x402 does not provide marketplace fulfillment, escrow, returns, or dispute resolution by itself",
      "description": "x402 is a payment protocol for charging clients over HTTP. Agentic commerce products still need separate marketplace state, seller controls, fulfillment, fraud handling, and post-payment dispute flows.",
      "severity": "medium",
      "status": "confirmed",
      "workaround": "Treat x402 as the payment layer. Pair it with marketplace application logic, indexed listing/payment state, admin controls, and explicit fulfillment/refund policies.",
      "citations": [
        {
          "url": "https://docs.cdp.coinbase.com/x402/",
          "quote": "x402 lets services monetize APIs and digital content onchain, allowing clients, both human and machine, to programmatically pay for access without accounts, sessions, or complex authentication.",
          "retrieved_at": "2026-06-03",
          "confidence": "medium",
          "algo": "sha256",
          "content_sha256": "36006e76b58d111287aefdb620e327194bc50b5803d5c4eed33dd2e706e0b239"
        }
      ]
    }
  ],
  "sources": [
    {
      "label": "x402 website",
      "url": "https://www.x402.org/",
      "type": "website"
    },
    {
      "label": "CDP x402 docs",
      "url": "https://docs.cdp.coinbase.com/x402/",
      "type": "docs"
    },
    {
      "label": "x402 Foundation GitHub",
      "url": "https://github.com/x402-foundation/x402",
      "type": "github"
    },
    {
      "label": "Seller quickstart",
      "url": "https://docs.cdp.coinbase.com/x402/quickstart-for-sellers",
      "type": "template"
    }
  ],
  "provenance": {
    "verified_at": "2026-06-03",
    "verified_by": "composewith.eth research (x402.org, CDP docs, and x402 Foundation GitHub live-verified via WebFetch 2026-06-03)",
    "confidence": "high"
  },
  "readiness_score": 89,
  "readiness_factors": [
    {
      "key": "docs_present",
      "points": 10,
      "max": 10,
      "detail": "Docs URL present"
    },
    {
      "key": "sdk_present",
      "points": 8,
      "max": 8,
      "detail": "SDK URL present"
    },
    {
      "key": "template_present",
      "points": 6,
      "max": 6,
      "detail": "Template/quickstart present"
    },
    {
      "key": "support_present",
      "points": 6,
      "max": 6,
      "detail": "Support channel present"
    },
    {
      "key": "capability_depth",
      "points": 13,
      "max": 20,
      "detail": "HTTP 402 payment flow: integration_workflow; Facilitator verification and settlement: production_surface"
    },
    {
      "key": "production_capability",
      "points": 15,
      "max": 15,
      "detail": "Has a production-ready capability"
    },
    {
      "key": "provenance_confidence",
      "points": 5,
      "max": 5,
      "detail": "Protocol provenance confidence is high"
    },
    {
      "key": "chain_coverage",
      "points": 6,
      "max": 10,
      "detail": "3 chain(s) (capped at 5)"
    },
    {
      "key": "freshness",
      "points": 10,
      "max": 10,
      "detail": "Last verified 7 day(s) ago"
    },
    {
      "key": "no_open_critical",
      "points": 10,
      "max": 10,
      "detail": "No open critical issues"
    }
  ],
  "readiness_caps": [],
  "scoring_version": "score.v2"
}