{
 "service": "Render check: proof for coding agents",
 "what": "A page measured in a real Chromium on Cloudflare Browser Run at the widths you name, N runs each: which element overflows and by how many pixels (clip-aware and transform-aware, so a clipped or turned box is not reported), layout shift and largest paint with the element behind each, console errors, WCAG AA contrast on the render, tap targets under 44 px, and screenshots. Medians with the spread. The answer is a receipt signed with Ed25519.",
 "doors": {
  "check": "GET https://proof.revasserlabs.com/v1/check?url=<page>&widths=390,1440&runs=3",
  "compare": "GET https://proof.revasserlabs.com/v1/compare?before=<page>&after=<page>&widths=390,1440&runs=3",
  "receipt": "GET https://proof.revasserlabs.com/v1/checks/<id>",
  "key": "GET https://proof.revasserlabs.com/.well-known/receipt-key.json",
  "mcp": "https://proof.revasserlabs.com/mcp (tools check_render, compare_render; x402 in the MCP message)",
  "mcp_edge": "https://proof.revasserlabs.com/mcp/edge (the same tools priced by HTTP 402 on the Mcp-Name header, the Monetization Gateway's shape)",
  "fixtures": [
   "https://proof.revasserlabs.com/fixtures/clipped",
   "https://proof.revasserlabs.com/fixtures/rotated",
   "https://proof.revasserlabs.com/fixtures/overflow",
   "https://proof.revasserlabs.com/fixtures/before",
   "https://proof.revasserlabs.com/fixtures/after"
  ]
 },
 "payment": {
  "network": "eip155:84532",
  "check_usd": "0.02",
  "compare_usd": "0.04",
  "note": "x402, test network (Base Sepolia) while the Monetization Gateway application is pending"
 },
 "limits": {
  "widths": "at most 3, each 320 to 1920",
  "runs": "1 to 10, default 3",
  "per_caller": "about six paid checks a minute (12 requests: an unpaid ask and its paid retry each count)"
 }
}