{"name":"onyx_preflight","tier":"metered","price_usdc":"0.02","endpoint":"https://onyx-actions.onrender.com/v1/onyx_preflight","method":"POST","input_schema":{"type":"object","properties":{"url":{"type":"string","description":"The x402-gated endpoint to preflight (http:// or https://)."},"timeout_seconds":{"type":"number","default":8.0,"description":"Probe timeout in seconds. Clamped to [2, 15]."}},"required":["url"]},"description":"Preflight safety check for an x402-gated endpoint, BEFORE you pay it. Probes the URL live (~8s timeout), confirms it actually speaks x402 (a proper HTTP 402 with a parseable payment-requirements body — not a decoy demanding payment in prose), parses the advertised price to human USDC, sanity-checks the payTo address (0x format + EIP-55 checksum) and network (mainnet vs silently-testnet), and flags dead/cold/zombie endpoints and absurd price traps. Returns one signed verdict — OK, WARN, or AVOID — plus every disclosed flag behind it. Sign facts, not judgments: each flag traces to a checkable rule, not an opaque trust score.","when_to_use":"An agent is about to call an unfamiliar x402-gated endpoint and wants to know, BEFORE spending USDC, whether it is alive, actually speaks x402 correctly, and is not a decoy, dead service, or price trap.","vs_alternatives":"x402station and rplryan/x402-discovery run a similar class of preflight check but return an unsigned result from a single vendor's opinion. Onyx returns the same check as a disclosed, Ed25519-signed verdict — every flag traces to a checkable rule (a status code, a parsed field, a regex), not an opaque trust score, and anyone can independently re-verify the signature.","example_request":{"url":"https://onyx-actions.onrender.com/mcp/","timeout_seconds":8},"example_response":{"url":"https://example.com/paid-endpoint","alive":true,"http_status":402,"x402_valid":true,"price_usdc":0.02,"pay_to":"0x1234...abcd","network":{"raw":"eip155:8453","chain":"Base","kind":"mainnet"},"flags":[],"verdict":"OK"},"settle_to":"0x3fD9ee1373562f894D322B37DFFAd7a5D2b2d78f","network":"base","facilitator":"https://facilitator.xpay.sh","payment_required":true,"free_introspection":true,"note":"GET this URL = free introspection card. POST with x402 payment header to call."}