{
  "format": "delx/intent-card/v1",
  "id": "x402-payment-preflight-api",
  "intent": "x402 Payment Preflight for an agent workflow",
  "title": "x402 Payment Preflight API for agents",
  "description": "Evaluate caller-supplied x402 payment requirements before a wallet signs them. Use after receiving HTTP 402 to enforce a maximum USDC amount, allowed networks, exact scheme, recipient presence, and an optional expiry buffer. Returns eligible accepts and explicit blockers for $0.002 USDC via x402 on Base; it never signs, pays, stores, or echoes a payment signature.",
  "keywords": [
    "x402 Payment Preflight API",
    "x402 Payment Preflight for agents",
    "pay per result API",
    "x402 API",
    "no API key"
  ],
  "updated_at": "2026-08-23",
  "canonical_url": "https://commerce.delx.ai/intents/x402-payment-preflight-api",
  "machine_url": "https://commerce.delx.ai/intents/x402-payment-preflight-api.json",
  "recommendation": {
    "tool_name": "util_x402_payment_preflight",
    "service_name": "x402 Payment Preflight",
    "method": "POST",
    "resource": "https://api.delx.ai/api/v1/x402/payment-preflight",
    "price_usdc": "0.002",
    "payment_protocols": [
      "x402",
      "mpp"
    ],
    "input_schema": {
      "type": "object",
      "properties": {
        "requirements": {
          "type": "object"
        },
        "max_amount_usdc": {
          "type": "number",
          "minimum": 0
        },
        "allowed_networks": {
          "type": "array",
          "minItems": 1,
          "maxItems": 20,
          "items": {
            "type": "string"
          }
        },
        "asset_decimals": {
          "type": "integer",
          "minimum": 0,
          "maximum": 18,
          "default": 6
        },
        "now_epoch_seconds": {
          "type": "integer",
          "minimum": 0
        },
        "min_expiry_seconds": {
          "type": "integer",
          "minimum": 0,
          "maximum": 86400,
          "default": 30
        }
      },
      "required": [
        "requirements",
        "max_amount_usdc",
        "allowed_networks"
      ],
      "additionalProperties": false
    },
    "example_input": {
      "requirements": {
        "accepts": [
          {
            "scheme": "exact",
            "network": "eip155:8453",
            "amount": "1000",
            "payTo": "0x1111111111111111111111111111111111111111",
            "expires": 1786272600
          }
        ]
      },
      "max_amount_usdc": 0.002,
      "allowed_networks": [
        "eip155:8453"
      ],
      "now_epoch_seconds": 1786272500
    },
    "example_output": {
      "schema": "delx/util-x402-payment-preflight/v1",
      "approved": true,
      "evaluated_count": 1,
      "eligible_count": 1,
      "selected": {
        "index": 0,
        "scheme": "exact",
        "network": "eip155:8453",
        "amount_usdc": "0.001",
        "pay_to": "0x1111111111111111111111111111111111111111",
        "expiry_status": "ok"
      },
      "evaluations": [
        {
          "index": 0,
          "scheme": "exact",
          "network": "eip155:8453",
          "amount_usdc": "0.001",
          "pay_to_present": true,
          "expiry_status": "ok",
          "blockers": []
        }
      ],
      "policy": {
        "max_amount_usdc": "0.002",
        "allowed_networks": [
          "eip155:8453"
        ],
        "asset_decimals": 6,
        "min_expiry_seconds": 30,
        "expiry_checked": true
      }
    },
    "agentcash": {
      "buy": "npx agentcash@latest fetch https://api.delx.ai/api/v1/x402/payment-preflight -m POST -H 'x-delx-source: intent-card-x402-payment-preflight-api' --max-amount 0.002 -b '{\"requirements\":{\"accepts\":[{\"scheme\":\"exact\",\"network\":\"eip155:8453\",\"amount\":\"1000\",\"payTo\":\"0x1111111111111111111111111111111111111111\",\"expires\":1786272600}]},\"max_amount_usdc\":0.002,\"allowed_networks\":[\"eip155:8453\"],\"now_epoch_seconds\":1786272500}'",
      "max_amount_usdc": "0.002"
    }
  },
  "attribution": {
    "header": "x-delx-source",
    "value": "intent-card-x402-payment-preflight-api"
  },
  "evidence": {
    "paid_openapi": "https://api.delx.ai/openapi.x402.json",
    "governed_portfolio": "https://api.delx.ai/x402-portfolio.json",
    "live_contract": "https://api.delx.ai/api/v1/x402/payment-preflight"
  }
}