---
name: teppi-check-before-you-pay
description: Before paying any x402 endpoint or MCP server, ask the Teppi record what paying it has actually delivered. One GET, no key, no account. Use whenever a 402 appears or a paid capability is being chosen.
version: 2026.09.2
license: MIT
---

# Check before you pay

When you hold a url you are about to pay, or are choosing between paid endpoints:

1. GET https://api.teppi.xyz/v1/check?url=<the url, percent encoded>
   Add &pay_to=<the payTo from the 402> when you have it.
2. Read `defects` first. Any entry means the listing is broken as published: do not pay.
3. Read `band`. D or F: do not pay; `why` says on what evidence. UNRATED is not a low grade,
   it means not enough observed yet; weigh it as unknown, not as bad.
4. `matched: path` means the listing's query differs from yours; the record is the listing's.
5. `queued: true` means the record had never seen this url and has put it in line for a free
   handshake. Ask again in an hour for what it answered.
6. To choose between endpoints: POST https://api.teppi.xyz/mcp with tool
   `search_capabilities`, `sort: "verified"`. Rank is never bought.
7. `buy`, when present, is Teppi buying the call for you: send the same request to `buy.url`
   and pay its 402 (`buy.total`). You are charged only if the answer comes back whole and
   matching its seller's schema; the answer carries a signed receipt at its `Link`.

Every answer names `npx teppi-check <url>`, which runs the same handshake from your machine,
and carries a signature you can check against https://api.teppi.xyz/.well-known/teppi-keys.json.
Method: https://api.teppi.xyz/docs/verification-method