{
 "acronym": "",
 "adoption": {
  "by": "x402 Foundation (x402.org live dashboard)",
  "level": "claimed",
  "probe_run": null
 },
 "aliases": [],
 "analog": "HTTP 402 Payment Required, finally implemented",
 "collisions": [],
 "discovery": {
  "mechanism": "HTTP 402 response carrying payment requirements in a header",
  "path": "none — signalled per-request via the 402 status code, not a fixed well-known path"
 },
 "dispute": null,
 "evidence": [
  {
   "claim": "x402's HTTP transport spec defines the 402 challenge as HTTP 402 status with a PAYMENT-REQUIRED header carrying a base64-encoded PaymentRequired object, and the client retry as a PAYMENT-SIGNATURE header carrying a base64-encoded PaymentPayload.",
   "date": null,
   "label": "VERIFIED",
   "url": "https://raw.githubusercontent.com/x402-foundation/x402/main/specs/transports-v2/http.md"
  },
  {
   "claim": "x402.org's footer identifies the project as 'x402 a Series of LF Projects, LLC', confirming Linux Foundation stewardship, and its Announcements page states the Linux Foundation announced the operational launch of the x402 Foundation on July 14, 2026.",
   "date": "2026-07-14",
   "label": "VERIFIED",
   "url": "https://x402.org/announcement"
  },
  {
   "claim": "x402.org's homepage displays a live self-reported dashboard: 75.41M transactions and $24.24M volume in the last 30 days, 94.06K buyers and 22K sellers, at time of check.",
   "date": "2026-09-06",
   "label": "VERIFIED",
   "url": "https://x402.org"
  }
 ],
 "form": "http-header",
 "governance": "x402 Foundation, a Series of LF Projects, LLC (Linux Foundation); operational launch announced 2026-07-14",
 "group": "HTTP 402 family",
 "history": [
  {
   "date": "2026-09-05",
   "note": "seeded from Exa Agent research run"
  },
  {
   "date": "2026-09-06",
   "note": "verified against x402.org (homepage, /announcement), x402-foundation/x402 specs/transports-v2/http.md"
  }
 ],
 "id": "x402",
 "implementation": "multi-implementation",
 "last_verified": "2026-09-06",
 "name": "x402",
 "native_status": "Open, neutral standard for internet-native payments",
 "origin": {
  "date": null,
  "org": "Coinbase"
 },
 "part_of": null,
 "parties": [
  "agent-site",
  "agent-payment"
 ],
 "phase": "living",
 "probe": {
  "method": "GET",
  "on_absent": "A 200 or a 402 without a PAYMENT-REQUIRED header means this specific path is not (or no longer) gated by x402 v2 over HTTP; the same origin could still use x402 over the MCP or other transports, or the legacy v1 header shape, so the probe only rules out v2/HTTP on the probed path.",
  "parse": "HTTP 402 status with a base64-encoded PaymentRequired object in the PAYMENT-REQUIRED response header (x402 v2 HTTP transport)",
  "path": "{origin}/{paid-path}"
 },
 "question": "How can an HTTP client pay per-request or per-resource, in stablecoins, without accounts, API keys, or signup?",
 "scope": "payments",
 "spec_url": "https://github.com/x402-foundation/x402/blob/main/specs/transports-v2/http.md",
 "step": "pay",
 "summary_md": "x402 is an open, HTTP-native payment protocol that activates the long-reserved (since 1999) HTTP 402 \"Payment Required\" status code: a server responds 402 with machine-readable payment requirements, the client pays (in practice, stablecoins over an EVM-compatible network) and retries the request with proof of payment attached [1]. It solves instant, account-free, per-request monetization for APIs and agentic consumers — no signup, no KYC, no stored API keys, no prepaid credit balance — collapsing what the project calls a five-step \"old way\" of API onboarding into three HTTP round trips [own site, x402.org homepage].\n\nIt does not itself define a payment network; it is a wire-format and challenge/response convention that networks and asset issuers plug into via a `scheme` and `network` field (the reference implementation targets EVM chains and USDC, per the transport spec's example payload) [1]. Version 2 of the specification moved the payment-required and payment-signature payloads into dedicated `PAYMENT-REQUIRED` and `PAYMENT-SIGNATURE` HTTP headers rather than embedding them in earlier v1 conventions, and the specification separately defines non-HTTP transports (the repository lists transports-v1 and transports-v2 directories) [1].\n\nAs of this verification, x402 is governed by the x402 Foundation, described in its own site footer as \"a Series of LF Projects, LLC\" — i.e., a Linux Foundation-hosted project — with an operational launch announced by the Linux Foundation on 2026-07-14 [2]. Coinbase originated the protocol; the Foundation now governs it independently of any single company, per the project's own framing [x402.org homepage]. The site's homepage displays a real-time usage dashboard claiming 75.41M transactions and $24.24M in volume over the trailing 30 days, with 94.06K buyers and 22K sellers, current as of this check [3] — but this figure is self-reported by the Foundation running the protocol, not measured by an independent index, so it is recorded here as claimed rather than observed or measured. What remains open: no independently operated adoption index (e.g. a third-party \"402 index\") was located and fetched during this verification to cross-check the Foundation's own dashboard number.",
 "track": "linux-foundation",
 "version": {
  "date": null,
  "label": "x402 protocol specification v2, transports-v2/http.md"
 },
 "url": "https://agenticweb.wiki/protocols/x402/",
 "category": "pay",
 "type": "protocol"
}