seller
A seller is the party that charges for a resource. x402 calls it the resource server: the HTTP server providing an API or other resource to a client. It sets the price, names the receiving address, and picks the facilitator that settles its payments.
The role is defined by what it operates. A resource server answers an unpaid request with a challenge, serves the request once payment is authorised, and chooses the facilitator it hands the signed payload to. Everything a client can see about a seller — the price, the network, the payTo address — is chosen by whoever controls that endpoint at the moment of the answer.
The other specifications name this side differently, and the words are not interchangeable. The commerce protocols say business or merchant, because a catalogue and an order stand behind the payment. A seller taking machine payments may have neither, and may be a single endpoint charging for a single thing.
For anything reading endpoints from outside, the seller is the operator of the address being read, and the reading shows no more than that. An endpoint's terms are evidence about that endpoint at that moment rather than about the party behind it.
→ probe402 publishes what each tracked endpoint answered — the tracked set is at the endpoint list.
Sources
- The x402 specification repositoryx402 Foundation
- The Agentic Commerce ProtocolAgentic Commerce Protocol
- Machine paymentsStripe documentation
Related buyer · facilitator · payTo · machine payment