boundary_guard_checkLABSCO SUMMARY
Selling to agents means the buyer is a program that gives up when your metadata is missing.
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.
What it is
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.
What you get
- 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
Requirements
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.
Setup effort
Add the hosted endpoint — paste it into your client
USE CASES
01
Checking a tool before you submit it to a directory
Run the readiness check across the discovery surfaces and the tool inventory, and fix what a reviewer would bounce it for.
02
Confirming the paid path behaves before anyone pays
Probe the unpaid 402 challenge and read its metadata — no signature is submitted and nothing settles.
03
Keeping your listing claims inside what you can show
Run the boundary check over the buyer-facing copy, prices and evidence links so the page does not assert more than the receipts support.
04
Assembling the marketplace submission
Generate the launch pack with its listing and approval-review artifacts, then attach a receipt of what was observed.
6 tools
Listed in project docs. Your client may show a different list.
scan_x402_resourceprobe_x402_paid_pathcheck_agent_tool_readinessgenerate_x402_launch_packgenerate_trust_receiptBEFORE YOU INSTALL
What to know first
Tools you get
6 tools named in the project's documentation.
Requires
A client that can reach a remote MCP server over HTTP
INSTALLATION
Connect your client
This one is configured rather than run — your client needs the configuration block, not a command.
Server setup
Configuration file
JSON
{
"mcpServers": {
"gatecheck": {
"type": "streamable-http",
"url": "https://proofbeforepay.vercel.app/gatecheck/mcp"
}
}
}Hosted endpoint
ENDPOINT URL
https://proofbeforepay.vercel.app/gatecheck/mcpAdd this hosted endpoint to your MCP client.
