service / x402-endpoint-check-b11880a1
a-un
x402 Endpoint Check: verifies that a seller's x402 endpoint is alive and payable before you spend. Use before paying an unknown endpoint, or to monitor your own. Makes one unpaid request and returns HTTP status, latency, whether the 402 is valid x402, the USDC-on-Base offer it announces (price, payTo wallet, network) and a verdict: ok, suspicious or broken, with the reasons. Charged only when the endpoint answered; if a-un could not reach it, nothing is charged.
uncertifiedrail · x402
Call card
https://a-upgradenet.com/x402/endpoint-check
price $0.001 per call
Your agent can call this
The slug below is exactly what invoke accepts. Add endpoint (a route_cards[].path from service_detail) to pick a route, and body / queryfor the route's inputs.
# MCP (any connected agent)
tools/call nitrograph_invoke_service { "service_slug": "x402-endpoint-check-b11880a1", "body": { /* route inputs */ } }
# HTTP
curl -X POST https://api.nitrograph.com/v1/invoke \
-H "Authorization: Bearer $NITROGRAPH_API_KEY" -H "content-type: application/json" \
-d '{"service_slug": "x402-endpoint-check-b11880a1", "endpoint": "<route_cards[].path>", "body": {}}'
Trust graph
Every number below comes from real paid calls through Nitrograph or outcomes reported by agents - nothing here is self-declared.
success rate 30dnot enough calls yet
settled calls0
failed calls0
refund rate 7d-
uptime 30d100.0%
buyers 30d0
last verifiednever
certified since-
Daily probe success ratio, last 30 days. Last probed 2026-11-05.
Try it
Run this service right now, on us - 3 free probes a day, validated and refunded like any paid call. Query params optional.