discover_servicesFree (kit)
Semantic search over the Bazaar index. Returns ranked candidates with payment config attached.
01What it is
Agentic layers / discovery layer
Find paid APIs.Call them on demand.
50+ services agents can discover and pay via x402 per call. Search a live catalog, resolve endpoints and payment terms, then invoke third-party services — no hard-coded vendor URLs required.
02Why
Why it matters
06
No more URL archaeology.
Prompts stay high-level. The agent searches; the kit returns ranked candidates with payment config attached.
Pay-per-call by design.
Every catalog entry is x402-monetized. Discovery is find, price, call, settle — not a static directory with billing elsewhere.
Agent-native workflow.
discover_services → get_service → paid_fetch. Multi-step flows without maintaining an internal service registry.
Works early in onboarding.
Catalog search does not require a bound wallet. Explore services before every end-user agent is fully provisioned.
Ecosystem scale.
Inherit new services as the Bazaar index grows — no redeployment needed per vendor.
No CDP key for search.
Public discovery API proxied by the kit. Production paid calls use wallet and x402 at call time.
Search once. Let your agent find, price, and call on demand.
03Flow
How it works
Search the catalog (discover_services)
Send a free-text query with optional filters — network, asset, maxUsdPrice, limit. Returns ranked services with payment config from the CDP x402 Bazaar.
Resolve one service (get_service)
Fetch a single entry by resource URL. Returns the confirmed endpoint, docs URL, and OpenAPI spec. Use to verify terms before spending.
Call and pay (paid_fetch)
Request the HTTPS resource. On 402, the MCP layer handles x402 signing and retry automatically. Returns the response body plus settlement metadata.
04Tools
Discovery tools
get_serviceFree (kit)
Exact lookup by resource URL. Confirm endpoint, docs, and payment terms before calling.
paid_fetchVariable (third party)
Probe then pay on x402 resources. HTTPS only. Pays the service operator per their advertised terms.
Use maxUsdPrice and network/asset filters in discover_services to control spend on variable third-party calls.
05Stack
How it fits the other layers
Agent Interface
Discovery tools run in the same MCP session as wallet and transfer tools. Tool descriptions guide discover → resolve → fetch.
Identity Layer
Registration declares x402Support. Identity answers who; Discovery answers what paid APIs this agent can use.
Discovery Layer
You are hereConnects agents to the x402 Bazaar: search, resolve, and paid_fetch for fifty-plus payable APIs without hard-coding vendor URLs.
Trust Layer
Spend caps apply to kit-priced tools. Steer variable third-party spend with maxUsdPrice and network filters in discover_services.
Payments Layer
Discovery surfaces payTo, network, and asset. paid_fetch and x402 v2 complete per-call settlement in stablecoins.
06Integrate
For developers
MCP tools: discover_services, get_service, paid_fetch. Optional env: CDP_X402_DISCOVERY_BASE, PAID_FETCH_HOST_ALLOWLIST.
// tools/call · discover_services
{
"query": "weather forecast",
"network": "base",
"maxUsdPrice": "0.01",
"limit": 5
}07FAQ
FAQ
Do I need a Coinbase CDP API key to search?
No. discover_services and get_service use the public Bazaar discovery API through the kit.
Can agents search before they have a wallet?
Yes. Catalog tools do not require a bound wallet. paid_fetch needs payment capability when the target returns 402.
How do I limit spend on discovered APIs?
Use maxUsdPrice and network/asset filters in discover_services. Kit spend policy covers fixed-price kit tools; variable third-party costs are controlled at search time.
08Start
Search fifty-plus payable APIs once. x402 per request, stablecoins on chain.