The x402 Bazaar vs. a trust layer
The x402 Bazaar is how most AI agents find x402 endpoints. It's run by Coinbase's CDP facilitator and lists every x402 service that has settled a payment through it: more than 23,000 resources, searchable by API, MCP and on agentic.market.
The Bazaar answers "what can I buy?" A trust layer like Lumière PayCheck answers "should I pay this one?" An agent that pays for APIs needs both. This page explains what each one does.
How an endpoint gets into the Bazaar
There's no sign-up form. A seller adds discovery metadata to their x402 server (a description, input and output schemas, an example), and the first time a buyer pays the endpoint through the CDP facilitator, it's indexed, usually within 15 minutes.
From then on:
- Search ranks by relevance and usage. The Bazaar's quality signal blends recent call volume, the number of unique payers over 30 days, and how complete the metadata is.
- Endpoints drop out when payments stop. A resource with no settled payment for 30 days is removed. So is one that stops answering
402 Payment Required. - A small curated set gets health checks. Featured endpoints need 99% availability and pass a health probe. Everything else is listed without one.
- Metadata is screened, mainly for text that could instruct an agent (prompt injection).
That's a solid discovery system. It's built to help agents find services, not to vouch for each one.
What the Bazaar doesn't tell an agent
| Question an agent should ask before paying | The Bazaar | Lumière PayCheck |
|---|---|---|
| Does this endpoint exist and charge in x402? | Yes | Yes |
| How many buyers use it? | Yes (calls and unique payers, 30 days) | Yes, plus how many are independent |
| Is it up right now? | Only for featured endpoints | Every endpoint, about every 30 minutes |
| When I pay, do I get what the listing promised? | No | Yes: we pay it and check the response |
| Did the price or payout wallet just change? | No | Yes, flagged before you pay |
| Is it a cheaper copy of a known seller? | No | Yes, lookalikes are flagged |
| Is this exact payment OK to send? | No | Yes: check_payment returns allow or deny for the amount and payTo in the quote |
| Endpoints outside the Bazaar? | No | Yes, added on request or found automatically |
The gap that matters most is the fourth row. Usage isn't the same as delivery: an endpoint can be popular and still return the wrong data. In 45,152 paid calls across 37,812 endpoints, 4.2% of endpoints returned a bad response after taking payment. The most common failure was a normal-looking 200 response missing the fields the listing promised. And half of all payment attempts didn't complete, mostly because the endpoint asked for payment again after being paid.
None of that shows up in a discovery listing.
How to use them together
- Find endpoints with the Bazaar (or any directory).
- Check the one you picked: look it up, or have your agent call
check_endpoint(free, API or MCP). - Before paying, send the 402 quote's amount, payTo, network and asset to
check_payment. Pay only ifallowistrue. - After paying, report the result with
report_outcome, so the next agent knows too.
See the integration guide for code, or browse every graded endpoint in the x402 seller directory.
For sellers
Being in the Bazaar gets you found. A PayCheck grade gets you trusted: agents that check before paying will prefer endpoints rated Proceed, which means a real paid test delivered. Get your endpoint tested, and if you sell outside the Bazaar, add your endpoint.