SchemaFetch

Schema-constrained web extract for AI agents. Pass a URL + preset (or JSON schema), get structured JSON back with confidence and source snippets. Pay per call in USDC on Base via x402 — no API keys for buyers.

Separate product from ReceiptStamp. Reuses the same Cloudflare account, CDP facilitator keys, and Base payTo wallet; does not merge codebases.

Live (after deploy): https://schemafetch.panmediatech.workers.dev

API

Route	Auth	Purpose
GET /health	free	Liveness + preset list
GET /v1/sample?preset=contact	free	Fixed demo HTML extract
GET /v1/presets	free	Preset schemas
GET /openapi.json	free	OpenAPI doc
POST /x402/extract	$0.02 USDC	{ "url", "preset" } or { "url", "schema" }
GET /x402/extract?url=&preset=	$0.02 USDC	Agentic.Market GET compatibility
POST /x402/extract/custom	$0.04 USDC	{ "url", "schema" } only

Presets

saas_pricing · contact · team · product · faq

Example (after payment)

POST /x402/extract
{
  "url": "https://example.com/pricing",
  "preset": "saas_pricing"
}

{
  "data": {
    "plans": [{ "name": "Pro", "price": "$29 / mo", "period": "month", "features": [] }],
    "currency_hints": ["USD"]
  },
  "confidence": 0.7,
  "sources": [{ "field": "plans", "quote": "..." }],
  "fetched_at": "2026-07-11T00:00:00.000Z",
  "cache": "miss",
  "preset": "saas_pricing"
}

Structure

• src/extract.js — pure extract logic (heuristics + presets)
• src/worker.mjs — Hono Worker + x402 paywall (CDP facilitator)
• mcp/server.mjs — MCP bridge (free tools + paid extract via x402-fetch)
• skills/schemafetch/SKILL.md — agent skill (when/how to call; free install)
• test/ — extract + worker tests (402 without real CDP settlement)
• scripts/bootstrap-x402-payment.mjs — one-time Bazaar first-settlement pay

MCP + skill (distribution, same monetization)

Packaging only — agents still pay the Worker per call. No second price.

You (the seller) do not need to keep npm run mcp open. The product is the live Worker + marketplace listing. MCP is how other people plug SchemaFetch into Claude Desktop / Cursor.

For buyers (your audience)

Step-by-step: mcp/FOR_USERS.md

One-liner config (Claude Desktop / similar hosts):

"schemafetch": {
  "command": "npx",
  "args": ["-y", "github:Fourier18/SchemaFetch", "mcp"],
  "env": {
    "SCHEMAFETCH_BASE_URL": "https://schemafetch.panmediatech.workers.dev",
    "X402_CLIENT_PRIVATE_KEY": "0xYOUR_BASE_PRIVATE_KEY_WITH_USDC"
  }
}

Skill

skills/schemafetch/SKILL.md — instructions agents can load (when to call, presets, budget).

Marketplace (agent HTTP discovery — already live)

https://agentic.market/services/schemafetch-panmediatech-workers-dev

Local

npm install
npm test

Deploy

Same Cloudflare account as ReceiptStamp (panmediatech workers.dev).

# Secrets — file redirect only on this machine (interactive paste can corrupt)
npx wrangler secret put CDP_API_KEY_ID < secrets/cdp_id.txt
npx wrangler secret put CDP_API_KEY_SECRET < secrets/cdp_secret.txt

npx wrangler deploy

Then once, with a funded Base USDC wallet, bootstrap Bazaar indexing:

X402_CLIENT_PRIVATE_KEY=0x... node scripts/bootstrap-x402-payment.mjs

Kill criterion

Zero non-test paid calls by 2026-07-25 = stop funding this product. Listing and self-payments do not count.

Relationship to ReceiptStamp

	ReceiptStamp	SchemaFetch
Job	Notarize payload	Extract structured page data
Rails	ACP + x402	x402 only (v1)
Worker	receiptstamp	schemafetch
payTo	0x7e05…dc20	same (by design)
CDP keys	Worker secrets	same account, new Worker secrets

See PLAN.md for status and deploy notes.

Built with

Language	JavaScript (Node.js ≥20, ESM Worker)
Runtime	Cloudflare Workers
HTTP	Hono
Payments	x402 + Coinbase CDP facilitator (USDC on Base)
Agent tools	MCP (@modelcontextprotocol/sdk), x402-fetch
AI (authoring)	Grok 4.5 via Grok Build CLI v0.2.93 (xAI SuperGrok / Grok Build agent stack)

Human owns product decisions, wallets, and accounts. Stack details also in TOOLS.md.