openapi: 3.2.0
info:
title: MERCURY x402 storefront Cited Metadata API
version: '1'
x-spec: mercury-storefront/1
description: Agent-payable resources over HTTP 402 (x402). LIVE — Base mainnet, real USDC, no token. Only currently-deliverable routes are listed (web-fetch is the live paid SKU; mints are gated off). Free discovery at /.well-known/x402, /x402/discovery, /catalog, and /manifest.
servers:
- url: https://network.mercury-hq.com
tags:
- name: cited-metadata
paths:
/buy/metadata:
get:
summary: MERCURY Cited Metadata
description: URL → one typed, SIGNED metadata record (JSON-LD + OpenGraph + Twitter-card + standard + canonical + title), by source. Deterministic, keyless, no LLM — the social-card/SEO/schema.org record an agent can PROVE.
operationId: buy_cited_metadata
tags:
- cited-metadata
responses:
'200':
description: Delivered after the x402 payment settles on Base mainnet.
content:
application/json:
schema:
type: object
properties:
ok:
type: boolean
description: true on success; false on an honest failure (you are NOT charged for ok:false)
url:
type: string
description: final URL after redirects
status:
type: integer
description: upstream HTTP status
fetchedAt:
type: string
description: ISO-8601 time the page was read
data:
type: object
description: the typed metadata record, by source
properties:
title:
type:
- string
- 'null'
description:
text
canonical:
type:
- string
- 'null'
description: href
openGraph:
type: object
description: all og:* / article:* / product:* meta, keyed by FULL property name (e.g. 'og:title')
additionalProperties:
type: string
twitter:
type: object
description: all twitter:* card meta
additionalProperties:
type: string
standard:
type: object
description: standard head meta (description, author, robots, viewport, charset, keywords, …)
additionalProperties:
type: string
jsonLd:
type: array
description: every parsed JSON-LD block (@graph flattened)
items:
type: object
counts:
type: object
description: how many signals of each class were found
properties:
jsonLd:
type: integer
openGraph:
type: integer
twitter:
type: integer
standard:
type: integer
text:
type: string
description: 'the canonical signed string: JSON.stringify(data, sortedKeys). The attestation signs THIS.'
error:
type: string
description: present only when ok:false
attestation:
type: object
description: EIP-191 provenance receipt over sha256(text)+url+status+time, verifiable OFFLINE by anyone (key pinned at /.well-known/mercury-attestation). Proves THIS metadata record is exactly what MERCURY parsed from THIS url at THIS time — the wedge a free metadata API cannot emit.
required:
- ok
- url
additionalProperties: false
'402':
description: Payment Required — retry with an x402-signed payment (e.g. x402-fetch). Terms are in the challenge body (x402 v1).
parameters:
- name: url
in: query
required: true
schema:
type: string
maxLength: 2048
description: the page to read metadata from (http/https)
description: the page to read metadata from (http/https)
x-payment-info:
protocols:
- x402
scheme: exact
price: $0.006
currency: USDC
network: base
networkCaip2: eip155:8453
testnet: false
asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
payTo: '0xe10B9d44e72A29B9c19da02981FFCd875308e3C1'
facilitator: https://api.cdp.coinbase.com/platform/v2/x402
x402Version: 1
x-x402:
scheme: exact
price: $0.006
currency: USDC
network: base
networkCaip2: eip155:8453
asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
payTo: '0xe10B9d44e72A29B9c19da02981FFCd875308e3C1'
facilitator: https://api.cdp.coinbase.com/platform/v2/x402
testnet: false
maxTimeoutSeconds: 60
x-payment-info:
protocols:
- x402
network: base
currency: USDC
payTo: '0xe10B9d44e72A29B9c19da02981FFCd875308e3C1'
facilitator: https://api.cdp.coinbase.com/platform/v2/x402
testnet: false
spec: mercury-storefront/1