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x402 Liveness Check
x402
x402 Liveness Check is a paid API for AI agents from proxy.suverse.io, paid per call via x402, $0.25/call, status unknown (last checked 2026-10-18).
Probes a target x402-protected URL and returns a liveness verdict (ALIVE/DEGRADED/DEAD) plus details about its 402 challenge surface, pricing, networks, and payTo — without sending any payment.
Price / call$0.25
Success—
StatusUnknown
How this service works
Probe any x402 resource URL without paying it: ALIVE/DEGRADED/DEAD verdict on its 402 surface - challenge validity, min price, networks, payTo, latency, bazaar extension. SSRF-guarded, no payment ever sent to the target. Auto-refund on failure.
Output
Returns a structured liveness verdict (ALIVE, DEGRADED, or DEAD) for the target x402 URL, along with details extracted from its 402 challenge: challenge validity, minimum price, accepted payment networks, payTo address, measured latency, and any bazaar extension metadata present. No payment is ever sent to the target.
Example use cases
Pre-integration x402 endpoint audit
“Before I start integrating this x402 API at https://market.someservice.io/v1/data/stream, can you check if it's alive and tell me its minimum price, supported networks, and whether the challenge looks valid? Don't pay anything.”
Diagnosing a suspected dead x402 service
“I think the x402 endpoint at https://provider.xyz/api/realtime-feed might be down — can you probe it and tell me if it's ALIVE, DEGRADED, or DEAD, and what latency you're seeing?”
Comparing x402 challenge parameters across providers
“Can you check the 402 challenge surface of https://feeds.databroker.io/v1/prices — specifically the payTo address, minimum price, and which networks it accepts — without triggering a payment?”
Technical details
Endpoint
POSThttps://proxy.suverse.io/v1/data/x402-liveness-check?utm_source=zero.xyzWhen to prefer
Use this endpoint when you need to verify that an x402-protected resource is healthy and correctly configured before integrating or paying it, or when you want to inspect its 402 challenge parameters (price, network, payTo) without committing any funds. Prefer this over generic HTTP health checkers when the target uses the x402 payment protocol, as it understands 402 challenge semantics specifically.
Side effects
- SSRF guard blocks private/internal IP targets — returns error if URL resolves to a non-public address
- Target URL is unreachable or times out — returns DEAD verdict with latency data
- Target does not return a 402 response — verdict may be DEGRADED or invalid challenge
- Malformed x402 challenge on target — returns DEAD or DEGRADED with challenge validity flag false
- Auto-refund issued if the check itself fails at the infrastructure level
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
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