Service directory

The HPP x402 directory is a curated catalog of paid x402 services on HPP. It's how an agent finds something to pay for without being handed a URL — the discovery layer that makes autonomous, agentic payments practical.

Public endpoint: https://x402-discovery.hpp.io

How listing works

You don't register a service by hand. The directory is facilitator-indexed:

1. A seller advertises discovery metadata on its 402 (the @x402 Bazaar extension does this; hpp-x402 serve does it by default).
2. On the service's first settled payment, the facilitator publishes the settlement and the directory indexes the service — its URL, price, scheme, network, and description.
3. It's now findable. Indexing follows the on-chain settlement, so a brand-new service appears shortly after its first sale, not instantly. Pass --private (or omit the metadata) to stay unlisted.

Because listing is driven by real settlements, the directory is a trust signal: entries are services that have actually been paid, not self-submitted claims.

Browse it

From an agent — the bridge exposes hpp_discover, so the agent searches the directory itself.

From the CLI:

hpp-x402 discover --limit 10                 # everything, newest first
hpp-x402 discover "compute" -t http          # search + filter by type
hpp-x402 discover --scheme upto              # only usage-based services

Each result shows type · scheme · price · network · URL · id. Pay one with hpp-x402 call <url-or-id>.

REST API

The directory is a read-only REST service — useful for building your own explorer or agent tooling.

Endpoint	Returns
GET /discovery/resources?type&network&limit&offset	a page of listed services
GET /discovery/search?q&type&network&limit	full-text + semantic search
GET /discovery/resources/:id	one service's full detail (metadata, schema, trust signals)

curl "https://x402-discovery.hpp.io/discovery/resources?type=http&limit=5"

Filters: type (http / mcp / a2a), network (CAIP-2, e.g. eip155:190415), and limit / offset for paging.

Related

• Pay from an AI agent — give an agent access to the directory.
• Quickstart: Sellers — get your service listed.
• How it works — the 402 flow and payment schemes.