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Mercury · Structured Extract

Extract$0.004 / callLivex402API key

GET /buy/extract

What it does

TYPED structured extract for autonomous agents — URL + schema → a clean, type-safe JSON record. Where /buy/fetch returns page TEXT (and ?extract= returns string-only fields), THIS returns the schema-conformant object an LLM/RAG/trading pipeline actually consumes: pass ?url=…&schema=title,price:number,rating:number,inStock:boolean and get back { title:"…", price:19.99, rating:4.5, inStock:true } — numbers as numbers, booleans as booleans, absent fields null (honest). `schema` accepts the URL-friendly compact form (field[:type], type in string|number|integer|boolean) OR a Firecrawl/OpenAI-style JSON-Schema object ({"properties":{"price":{"type":"number"}}}). That is Firecrawl's paid 'JSON mode' headline guarantee — type-safety, 'numbers as numbers not strings' — done DETERMINISTICALLY from the page's own JSON-LD/OpenGraph/meta/microdata: keyless, NO LLM call, NO API key, NO signup, $0.004/call, paid in-band over HTTP 402 (x402, USDC on Base mainnet). The typed record is folded into the SIGNED provenance attestation too (EIP-191, ecrecoverable OFFLINE), so a buyer can prove the EXTRACTED FIELDS — not just raw bytes — are exactly what MERCURY resolved. Honest charge-per-ATTEMPT: every call returns a structured result (success OR an ok:false reason). Same SSRF guard, 5s timeout, 10MB cap, no mint.

The goal it serves: turn a page into a typed record an agent can act on, with the signed receipt proving the fields are exactly what Mercury resolved from the source — deterministic, keyless, no LLM.

Schemas & output preview

Input schema — the exact request shape the route validates.

json · input schema

{
  "type": "object",
  "properties": {
    "url": {
      "type": "string",
      "maxLength": 2048,
      "description": "the page to extract from (http/https)"
    },
    "schema": {
      "type": "string",
      "maxLength": 1024,
      "description": "fields to extract. COMPACT: comma list of field[:type] (type in string|number|integer|boolean, default string), e.g. title,price:number,rating:number,inStock:boolean. OR a JSON-Schema string ({\"properties\":{\"price\":{\"type\":\"number\"}}}). Resolved from JSON-LD/OpenGraph/meta/microdata."
    },
    "format": {
      "type": "string",
      "enum": [
        "text",
        "markdown"
      ],
      "description": "optional: text (default) or markdown for the page-text field"
    }
  },
  "required": [
    "url",
    "schema"
  ],
  "additionalProperties": false
}

Output schema — the exact response shape the handler returns.

json · output schema

{
  "type": "object",
  "properties": {
    "ok": {
      "type": "boolean",
      "description": "true on success; false on an honest failure (still delivered)"
    },
    "url": {
      "type": "string",
      "description": "final URL after redirects"
    },
    "status": {
      "type": "integer",
      "description": "upstream HTTP status"
    },
    "extract": {
      "type": "object",
      "description": "the TYPED record: each requested field resolved + coerced to its declared type (numbers as numbers, booleans as booleans), absent fields null. Deterministic, keyless, no LLM.",
      "additionalProperties": {
        "type": [
          "string",
          "number",
          "boolean",
          "null"
        ]
      }
    },
    "schema": {
      "type": "object",
      "description": "echo of the resolved field->type map that was applied",
      "additionalProperties": {
        "type": "string"
      }
    },
    "coerced": {
      "type": "array",
      "description": "names of the fields that were actually type-cast (present only when non-empty)",
      "items": {
        "type": "string"
      }
    },
    "title": {
      "type": "string",
      "description": "page <title>"
    },
    "text": {
      "type": "string",
      "description": "cleaned page text (also returned; markdown if ?format=markdown)"
    },
    "bytes": {
      "type": "integer",
      "description": "raw body size"
    },
    "contentType": {
      "type": "string"
    },
    "truncated": {
      "type": "boolean"
    },
    "redirects": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "redirect chain followed"
    },
    "fetchedAt": {
      "type": "string",
      "description": "ISO timestamp of the fetch (also in the signed attestation)"
    },
    "metered": {
      "type": "boolean"
    },
    "delivered": {
      "type": "string"
    },
    "kind": {
      "type": "string"
    },
    "error": {
      "type": "string",
      "description": "present only when ok:false"
    },
    "attestation": {
      "type": "object",
      "description": "EIP-191 provenance receipt over the page text + the typed extract record (canonical key order), ecrecoverable OFFLINE (key at /.well-known/mercury-attestation). Proves the FIELDS are genuine + untampered.",
      "properties": {
        "keyId": {
          "type": "string"
        },
        "alg": {
          "type": "string"
        },
        "address": {
          "type": "string"
        },
        "contentHash": {
          "type": "string"
        },
        "nonce": {
          "type": "string"
        },
        "signedAt": {
          "type": "string"
        },
        "signature": {
          "type": "string"
        },
        "verify": {
          "type": "object",
          "properties": {
            "message": {
              "type": "string"
            },
            "howTo": {
              "type": "string"
            }
          }
        }
      }
    }
  },
  "required": [
    "ok",
    "url"
  ],
  "additionalProperties": false
}

Output preview — a real example response, shown free (you only pay when you call the route).

json · output preview

{
  "ok": true,
  "url": "https://example.com/",
  "status": 200,
  "title": "Example Domain",
  "extract": {
    "title": "Example Domain",
    "price": null,
    "inStock": null
  },
  "schema": {
    "title": "string",
    "price": "number",
    "inStock": "boolean"
  },
  "contentType": "text/html; charset=utf-8",
  "truncated": false,
  "attestation": {
    "keyId": "mercury-x402-attestation-v1:0x<signer>",
    "alg": "EIP-191-personal_sign",
    "address": "0x<signer-from-/.well-known/mercury-attestation>",
    "contentHash": "0x<sha256 of text+extract>",
    "nonce": "0x<16-random-bytes>",
    "signedAt": "2026-06-03T00:00:00.000Z",
    "signature": "0x<65-byte EIP-191 signature>",
    "verify": {
      "message": "mercury-x402:fetch-attestation:v1\nurl=https://example.com/\nstatus=200\nsha256=0x…\nfetchedAt=2026-06-03T00:00:00.000Z\nnonce=0x…",
      "howTo": "EIP-191 ecrecover this message; signer must equal address. Recompute sha256(text+extract)==contentHash."
    }
  }
}

Pay & call

Your agent calls the route; the 402 challenge carries the exact price ($0.004, USDC on Base mainnet); the x402 client settles via the CDP facilitator and retries. No key, no signup.

agent.mjs · x402

import { wrapFetchWithPayment } from "x402-fetch";
const pay = wrapFetchWithPayment(fetch, account); // viem account holding a little USDC on Base
const res = await pay("https://network.mercury-hq.com/buy/extract?url=https://example.com&schema=id:integer,name,price:number");
const out = await res.json(); // the result + `attestation` (the signed receipt)

Prepaid alternative — the same route accepts an API key:

bash · API key

# Same route, prepaid API-key rail (Bearer mk_live_…) — get a key at https://network.mercury-hq.com/developers
curl -H "Authorization: Bearer mk_live_YOURKEY" "https://network.mercury-hq.com/buy/extract?url=https://example.com&schema=id:integer,name,price:number"

Pay over 402 — get the missing pieceEvery paid call returns an EIP-191 signed receipt — verify it free at /x402/verify.

Verify the receipt

Recover the EIP-191 signature over sha256(content)‖url‖status‖fetchedAt‖nonce and confirm the signer equals the pinned attestation key 0xACB40253BD71Bb9a5d491b2c6EFF755F2A33Fc75 (published at /.well-known/mercury-attestation). No callback to Mercury — the receipt verifies offline, forever. Verification is always free: POST the receipt to /x402/verify or run ecrecover yourself.

Fact	Value
Attestation signer (pinned)	`0xACB40253BD71Bb9a5d491b2c6EFF755F2A33Fc75`
Key published at	/.well-known/mercury-attestation
Live verifier (free)	/x402/verify
Settlement	real USDC on Base mainnet (eip155:8453) via CDP — auditable on BaseScan

Cited Feed

$0.005

RSS/Atom feed URL → a SIGNED, normalized item list [{title,link,published,summary}] unified across RSS 2.0/RDF + Atom 1.0: CDATA unwrapped, HTML…

Open

Cited Links

$0.005

URL → a SIGNED outbound/internal link graph: every <a href> as an absolute URL + anchor text, classified internal vs external against the page…

Open

Cited Metadata

$0.006

URL → one typed, SIGNED metadata record (JSON-LD + OpenGraph + Twitter-card + standard <meta> + canonical + title), by source. Deterministic,…

Open

Cited Table

$0.006

URL in → the page's main HTML <table>(s) parsed into typed, header-keyed rows (JSON) + clean RFC-4180 CSV, with a signed provenance receipt over the…

Open

More: all services · /catalog · the headline web-fetch · agent twin of this page: GET /university/docs/extract?format=md

Mercury · Structured Extract

What it does

Schemas & output preview

Pay & call

Verify the receipt

Related

Cited Feed

Cited Links

Cited Metadata

Cited Table