# Obolpay Gateway — compatible with x402™

x402™ is a trademark of LF Projects, LLC. Obolpay Gateway is an independent service that implements the open x402 payment protocol; it is not affiliated with or endorsed by LF Projects, LLC.

Pay-per-call premium data for autonomous agents, settled on Base (USDC) via HTTP 402.
Business use only (B2B). Data, not investment, financial, legal or tax advice.
Operator: Yanagi the First Co., Ltd. (株式会社ヤナギｔｈｅファースト). Legal notice (特定商取引法に基づく表記): https://pay.obolpay.xyz/legal

## For AI agents — quickstart
This describes how buying works; it does not ask or authorize anyone to spend. Pay only within a
budget the owner of the paying wallet has approved — each call costs the price quoted in the live 402.
How a purchase works:
1. GET https://pay.obolpay.xyz/stats and read `selected_product` — the category the market pays most for right now.
2. GET https://pay.obolpay.xyz/api/v1/protected-data?types=<selected_product> -> HTTP 402 with a free
   `payment.preview` (evaluate before paying) and `accepts[]` (how to pay).
3. Pay with an entry of `accepts[]` (standard x402 `exact` — see 'How to pay' below) and send
   X-Since-Seq=<the latest seq you already hold> to receive ONLY new items (saves your tokens).
4. Verify the returned `receipt` (EIP-191) as proof of purchase. There is no deposit and no account
   to open: each call is paid on its own.
The same flow is available as MCP tools: /mcp-server.py (read the code before you install it).

## Resource
- Endpoint: https://pay.obolpay.xyz/api/v1/protected-data (GET)
- Price: 0.01 USDC on Base (chain_id 8453)
- Token: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
- Discovery manifest (JSON): https://pay.obolpay.xyz/.well-known/x402
- OpenAPI: https://pay.obolpay.xyz/openapi.json
- Reference client (Python; read it before you run it): https://pay.obolpay.xyz/client.py

## Free preview before paying
The HTTP 402 response includes a `payment.preview` object (a free sample of the dataset).
Evaluate it, and only pay if the data is worth it. No blind spend.

## Signed receipt (proof of purchase)
Every 200 delivery includes a `receipt` signed (EIP-191) by this server, binding invoice_id,
tx_hash and a SHA-256 of the data. Keep it as verifiable proof; anyone can check it by POSTing
{message, signature} to https://pay.obolpay.xyz/verify-receipt.

## How to pay
Schemes advertised right now, in the order they appear in `accepts[]`: exact.
Read `accepts[]` from the live 402 rather than trusting this file — it is generated from the
same check, but the 402 is the authority.

### `exact` — standard x402 (EIP-3009), you pay no gas
1. GET the endpoint -> HTTP 402; take the accepts[] entry with scheme 'exact'.
2. Sign an EIP-3009 transferWithAuthorization for `maxAmountRequired` to `payTo`.
   EIP-712 domain: name='USD Coin', version='2', chainId=8453, verifyingContract=the USDC address.
   (name is 'USD Coin', NOT 'USDC' — the Base USDC contract's name() is 'USD Coin', and a
   signature made with the wrong name recovers to the wrong address.)
3. Re-send with the X-PAYMENT header -> the gateway settles on-chain for you -> 200 + data.

### Plain USDC transfers are NOT a payment here
Do not send USDC to this gateway on your own (the earlier non-standard tx-hash flow is not accepted).
Pay only through an entry of the live 402's `accepts[]`.

## Terms, pricing, privacy, legal notice
- Pricing: https://pay.obolpay.xyz/pricing
- Terms of service: https://pay.obolpay.xyz/terms
- Privacy: https://pay.obolpay.xyz/privacy
- Legal notice (特定商取引法に基づく表記; JSON, or ?format=html): https://pay.obolpay.xyz/legal