This runs that inspection from the outside and reports what it actually observed, then says plainly what a receipt cannot prove. The unpaid 402 path is the useful part: the payment challenge is exercised without any money moving.
A readiness check for people selling agent tools. It inspects the public surfaces a buyer or a directory would look at, exercises the unpaid side of an x402 payment challenge, and produces the artifacts a marketplace submission asks for. Six tools, with the inventory itself public so a directory can inspect it before calling anything.
- Product-scoped discovery checked end to end: homepage, llms.txt, agents.txt, product card, skill card, sitemap and MCP server card
- Your MCP inventory read the way a buyer reads it, through public initialize and tools/list
- The unpaid 402 challenge and its metadata exercised — no payment signature submitted, no funds moved
- Listing readiness reviewed: buyer-facing copy, prices, evidence links and where the claims stop
- A launch pack generated as submission and approval-review artifacts, which publishes no listing and contacts nobody
- A trust receipt over what was actually observed — public metadata, unpaid 402 behaviour, request summaries, hashes and the artifacts returned
Nothing to install: point a client at https://proofbeforepay.vercel.app/gatecheck/mcp over streamable-http. Initialize and tools/list are public; direct production tool execution may want a bearer token. The reports and receipts are bounded on purpose — they evidence observed metadata and unpaid 402 behaviour, and claim nothing about endorsement, settlement, security certification, custody, KYC coverage or buyer adoption.
One command — npx -y mcp-remote https://x402-resource-scanner.vercel.app/gatecheck/mcp