Hiroshi-Ichiyanagi/obolpay-x402-mcp

> Status (2026-10-06): maintenance. Since 2026-09-24 the Obolpay gateway accepts payments only through the standard x402 exact scheme (EIP-3009 transferWithAuthorization). This package and the buy examples still use the older pay-then-unlock flow, so they cannot buy at the moment — they stop before sending any USDC, because the gateway no longer quotes a recipient for that flow. Prepaid top-ups (topup()) ended on 2026-09-24 as well. discover(), preview() and verifyreceipt() still work. To buy, use a standard x402 client against https://pay.obolpay.xyz (the gateway's own reference client: https://pay.obolpay.xyz/client.py).
> 📖 Tutorial (written for the older prepaid flow — see the status note above): Let your AI agent autonomously buy data — x402 + gasless prepaid + MCP on Base
MCP server for the live Obolpay x402 gateway — pay-per-call premium data for AI agents, settled in USDC on Base mainnet via HTTP 402. Business use only (see the gateway's terms).
Give any MCP-compatible agent (Claude Desktop, etc.) the ability to discover → evaluate (free preview) → verify a signed receipt (buying: see the status note above).
## 🚀 Copy-paste examples (start here) → examples/
No MCP needed to try it. Zero setup, no wallet, stdlib only:
bash
python3 examples/quickstartpreview.py # evaluate the data QUALITY for free (trustless preview)
The buy examples (buyopenunit.py, agenttool.py) use the older
pay-then-unlock flow and cannot buy since 2026-09-24 (see the status note). Full walkthrough: examples/README.md.
## Tools
| Tool | What it does | Status (2026-10-06) |
| discover() | Machine-readable service manifest (price, token, network, capabilities) | works |
| preview() | Free data sample + price from the 402 challenge (no spend) | works |
| purchase() | One-shot on-chain pay-and-fetch | cannot buy since 2026-09-24 (stops before paying) |
| topup(txhash) | Fund a prepaid balance from a USDC deposit (once) | ended 2026-09-24 (the gateway answers 410) |
| balance(address) | Balance, calls remaining, next nonce | works — the balance now holds only SLA and warranty credits |
| spendgasless() | Instant, gasless pay-per-call from the prepaid balance (no on-chain tx/gas) | spends SLA and warranty credits only |
| verifyreceipt(message, signature) | Third-party verify a proof-of-purchase receipt | works |
## Why it's different
Free preview before paying — evaluate the data, no blind spend.
Signed receipts — EIP-191 proof-of-purchase, verifiable at /verify-receipt.
Freshness SLA — stale data earns a credit to a non-refundable, non-transferable account balance at the gateway (spendable via signed vouchers).
Delta delivery (X-Since-Seq) — only new items, saves your context tokens.