onyx_preflight
ActiveTool of onyx-paid-mcp
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. (price: $0.02 USDC, tier: metered)
Parameters schema
{
"type": "object",
"required": [
"url"
],
"properties": {
"url": {
"type": "string",
"description": "The x402-gated endpoint to preflight (http:// or https://)."
},
"timeout_seconds": {
"type": "number",
"default": 8,
"description": "Probe timeout in seconds. Clamped to [2, 15]."
}
}
}Parent server
onyx-paid-mcp
https://github.com/dimitrilaouanis-tech/onyx-mcp
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