service / x402-x402-endpoint-preflight-87154cb9

x402 Endpoint Buyer Preflight

Verify and lint a third-party x402 endpoint without paying it. Probe the live HTTP 402 challenge, validate x402 v2 and Base payment requirements, and check exact Coinbase Bazaar and 402index listing evidence before a buyer authorizes payment.

uncertifiedrail · x402

Call card

https://ai-data-marketplace-1042299154756.us-central1.run.app/api/v1/x402_endpoint_preflight price $0.003 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-x402-endpoint-preflight-87154cb9", "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-x402-endpoint-preflight-87154cb9", "endpoint": "<route_cards[].path>", "body": {}}'

Reliability

uptime 30d-
refund rate 7d-
settled calls0
failed calls0
certified since-
2026-08-17: 100% ok2026-08-18: 100% ok2026-08-19: 100% ok2026-08-20: 100% ok2026-08-21: 100% ok2026-08-22: 100% ok2026-08-23: 100% ok2026-08-24: 100% ok2026-08-25: 100% ok2026-08-26: 100% ok

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.