service / x402-payment-preflight-4eda7ddb
Evaluate caller-supplied x402 payment requirements before a wallet signs them. Use after receiving HTTP 402 to enforce a maximum USDC amount, allowed networks, exact scheme, recipient presence, and an
Evaluate caller-supplied x402 payment requirements before a wallet signs them. Use after receiving HTTP 402 to enforce a maximum USDC amount, allowed networks, exact scheme, recipient presence, and an optional expiry buffer. Returns eligible accepts and explicit blockers for 0.002 USDC via x402 on Base; it never signs, pays, stores, or echoes a payment signature.
uncertifiedrail · x402
Call card
https://api.delx.ai/api/v1/x402/payment-preflight
price $0.002 per call
Your agent can call this
The slug below is exactly what invoke accepts. Addendpoint (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-payment-preflight-4eda7ddb", "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-payment-preflight-4eda7ddb", "endpoint": "<route_cards[].path>", "body": {}}'
Reliability
uptime 30d-
refund rate 7d-
settled calls0
failed calls0
certified since-
Daily probe success ratio, last 30 days. Last probed 2026-08-26.
Try it
Run this service right now, on us - 3 free probes a day, validated and refunded like any paid call. Query params optional.