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service / x402-preflight-41148d41

PennyAPI x402 Seller Preflight

Preflight an unfamiliar x402 paid API before spending. Validate the live 402 payment challenge, network, USDC asset, amount, payTo recipient, TLS, redirects, manifest presence, latency, and provenance. Returns deterministic GO/REVIEW/STOP and never signs or sends payment to the inspected seller.

uncertifiedrail · x402

Call card

https://pennyregwatch.com/v1/x402/preflight 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-preflight-41148d41", "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-preflight-41148d41", "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-
2026-09-27: 100% ok2026-09-28: 100% ok2026-09-29: 100% ok2026-09-30: 100% ok2026-10-01: 100% ok2026-10-02: 100% ok2026-10-03: 100% ok2026-10-04: 100% ok2026-10-05: 100% ok2026-10-06: 100% ok2026-10-07: 100% ok2026-10-08: 100% ok2026-10-09: 100% ok2026-10-10: 100% ok2026-10-11: 100% ok2026-10-12: 100% ok

Daily probe success ratio, last 30 days. Last probed 2026-10-12.

Try it

Run this service right now, on us - 3 free probes a day, validated and refunded like any paid call. Query params optional.