{
  "kind": "x402-first-buy",
  "branding": "DevVizion Agent Utilities",
  "version": "0.3.77",
  "at": "2026-07-23T20:12:52.789Z",
  "purpose": "Executable settle card for agent wallets that already decided to pay. Free sample first, then unpaid POST → 402 → X-PAYMENT retry.",
  "origin": "https://x402.devvizion.com",
  "scheme": "exact",
  "network": "eip155:8453",
  "chainId": 8453,
  "asset": "USDC",
  "assetAddress": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "payTo": "0xE79e7fa7Ce7259C46F9B127b837d2907Bb036F95",
  "facilitator": "cdp",
  "facilitatorUrl": "https://api.cdp.coinbase.com/platform/v2/x402",
  "paymentHeader": "X-PAYMENT",
  "freeSample": {
    "method": "GET",
    "url": "https://x402.devvizion.com/v0/sample-outline.json?topic=x402",
    "markdownUrl": "https://x402.devvizion.com/v0/sample-outline?topic=x402",
    "mcpTool": "x402_sample_outline",
    "priceUsdc": "0"
  },
  "firstBuy": {
    "method": "POST",
    "path": "/v0/outline",
    "url": "https://x402.devvizion.com/v0/outline",
    "body": {
      "topic": "x402 agent research"
    },
    "priceUsdc": "0.01",
    "amountAtomic": "10000",
    "maxAmountRequired": "10000",
    "maxTimeoutSeconds": 120,
    "mcpTool": "x402_research_outline",
    "contentType": "application/json",
    "unpaidExpect": {
      "status": 402,
      "note": "accepts[] / PAYMENT-REQUIRED with payTo + maxAmountRequired"
    },
    "paidExpect": {
      "status": 200,
      "contentType": "text/markdown",
      "note": "full research outline markdown"
    }
  },
  "upgrade": {
    "method": "POST",
    "path": "/v0/brief",
    "url": "https://x402.devvizion.com/v0/brief",
    "body": {
      "topic": "x402 agent research"
    },
    "priceUsdc": "0.02",
    "amountAtomic": "20000",
    "maxAmountRequired": "20000",
    "mcpTool": "x402_research_brief"
  },
  "settle": [
    "GET https://x402.devvizion.com/v0/sample-outline.json?topic=x402  (free smoke)",
    "POST https://x402.devvizion.com/v0/outline unpaid → HTTP 402 + accepts[]",
    "Build X-PAYMENT exact · Base eip155:8453 · USDC · payTo · amount 10000",
    "Retry same POST with header X-PAYMENT → 200 markdown outline",
    "Optional upgrade POST https://x402.devvizion.com/v0/brief → 0.02 USDC"
  ],
  "curl": {
    "free": "curl -s \"https://x402.devvizion.com/v0/sample-outline.json?topic=x402\"",
    "unpaid": "curl -s -i -X POST \"https://x402.devvizion.com/v0/outline\" \\\n  -H \"content-type: application/json\" \\\n  -d '{\"topic\":\"x402 agent research\"}'",
    "paid": "curl -s -i -X POST \"https://x402.devvizion.com/v0/outline\" \\\n  -H \"content-type: application/json\" \\\n  -H \"X-PAYMENT: <base64 payment payload from 402 accepts[]>\" \\\n  -d '{\"topic\":\"x402 agent research\"}'"
  },
  "mcp": {
    "url": "https://x402.devvizion.com/mcp",
    "freeTool": "x402_sample_outline",
    "firstPaidTool": "x402_research_outline",
    "upgradeTool": "x402_research_brief"
  },
  "related": {
    "buyerMd": "https://x402.devvizion.com/buyer.md",
    "pitchJson": "https://x402.devvizion.com/pitch.json",
    "sampleOutlineJson": "https://x402.devvizion.com/v0/sample-outline.json?topic=x402",
    "wellKnown": "https://x402.devvizion.com/.well-known/x402",
    "hirePath": "https://x402.devvizion.com/hire-path.json",
    "self": "https://x402.devvizion.com/first-buy.json"
  },
  "oneLiner": "First buy: free GET https://x402.devvizion.com/v0/sample-outline.json → unpaid POST /v0/outline → 402 → pay 0.01 USDC Base to 0xE79e7fa7Ce7259C46F9B127b837d2907Bb036F95 → retry X-PAYMENT. Machine: https://x402.devvizion.com/first-buy.json"
}