MERCURY
University›Docs›Fetch›Cited Markdown

Mercury · Cited Markdown

Fetch$0.005 / callLivex402API key

GET /buy/markdown

What it does

URL → clean, LLM-ready markdown (boilerplate/nav/ads stripped, headings + lists + links preserved) with a signed provenance receipt pinning the markdown to its source — the RAG-ingest primitive. Deterministic (no LLM): same URL + same source bytes ⇒ byte-identical markdown.

The goal it serves: give an agent provable web content — the bytes PLUS a portable, offline-verifiable proof of what/where/when — so RAG stores, research pipelines and downstream agents can cite evidence, not hearsay.

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 convert to markdown (http/https)"
    }
  },
  "required": [
    "url"
  ],
  "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 (503-before-charge)"
    },
    "url": {
      "type": "string",
      "description": "final URL after redirects"
    },
    "status": {
      "type": "integer",
      "description": "upstream HTTP status"
    },
    "text": {
      "type": "string",
      "description": "the canonical clean MARKDOWN (the string the signed receipt pins) — boilerplate/nav/ads stripped, headings + lists + links preserved. Identical to data.markdown."
    },
    "fetchedAt": {
      "type": "string",
      "description": "ISO-8601 fetch time (also folded into the signed receipt)"
    },
    "data": {
      "type": "object",
      "description": "the structured deliverable the buyer consumes",
      "properties": {
        "markdown": {
          "type": "string",
          "description": "clean LLM-ready markdown (== text)"
        },
        "title": {
          "type": "string",
          "description": "page <title> (HTML pages only)"
        },
        "wordCount": {
          "type": "integer",
          "description": "word count of the markdown (for chunk/cost budgeting)"
        },
        "contentType": {
          "type": "string"
        },
        "bytes": {
          "type": "integer",
          "description": "raw upstream body size"
        },
        "truncated": {
          "type": "boolean",
          "description": "true if the markdown hit the 200KB cap"
        },
        "redirects": {
          "type": "array",
          "items": {
            "type": "string"
          },
          "description": "redirect chain followed"
        }
      },
      "additionalProperties": false
    },
    "error": {
      "type": "string",
      "description": "present only when ok:false"
    }
  },
  "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,
  "text": "Example Domain\n\n# Example Domain\n\nThis domain is for use in documentation examples without needing permission. Avoid use in operations. [Learn more](https://iana.org/domains/example)",
  "fetchedAt": "2026-06-04T00:00:00.000Z",
  "data": {
    "markdown": "Example Domain\n\n# Example Domain\n\nThis domain is for use in documentation examples without needing permission. Avoid use in operations. [Learn more](https://iana.org/domains/example)",
    "title": "Example Domain",
    "wordCount": 22,
    "contentType": "text/html; charset=utf-8",
    "bytes": 513,
    "truncated": false,
    "redirects": []
  }
}

Pay & call

Your agent calls the route; the 402 challenge carries the exact price ($0.005, 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/markdown?url=https://example.com");
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/markdown?url=https://example.com"
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.

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

Verifiable Web Fetch

$0.003
VERIFIABLE keyless web-read for autonomous agents. Every result ships a cryptographically SIGNED provenance receipt (EIP-191 over…
Open

Cited Batch

$0.02
List of URLs (≤20) → clean content for each + ONE signed receipt committing to a MERKLE ROOT over every page's contentHash. Tamper-evident multi-page…
Open

Cited Readability

$0.005
URL → a clean ARTICLE record { title, byline, publishedAt, article text } with boilerplate (nav/header/footer/sidebar/ads/share-bars/comment-forms)…
Open

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