GateCheck
A remote MCP server that verifies paid x402 and MCP tools for discoverability, inspectability, and claim-bound correctness, enabling pre-submission readiness checks for agent-tool sellers.
README
GateCheck by LarryBuildsAI
GateCheck is a hosted remote MCP server and x402 readiness surface for paid agent-tool sellers.
Use it before public submission, promotion, or paid agent routing to verify that a paid x402 or MCP tool is discoverable, inspectable, and claim-bounded.
Hosted MCP Endpoint
- Remote MCP URL:
https://proofbeforepay.vercel.app/gatecheck/mcp - Transport:
streamable-http - Public introspection:
initializeandtools/list - Protected tool execution: bearer auth may be required for direct production calls
- Product homepage:
https://proofbeforepay.vercel.app/gatecheck - Scorecard:
https://github.com/LarryLemonBot/gatecheck/blob/main/scorecard.md - Product card:
https://proofbeforepay.vercel.app/gatecheck/product-card.md - Marketplace index:
https://proofbeforepay.vercel.app/gatecheck/marketplaces.json
MCP Client Config
{
"mcpServers": {
"gatecheck": {
"type": "streamable-http",
"url": "https://proofbeforepay.vercel.app/gatecheck/mcp"
}
}
}
If your client supports request headers and you have a GateCheck production token, add:
{
"Authorization": "Bearer YOUR_GATECHECK_TOKEN"
}
Do not put private keys, wallet secrets, cookies, customer data, or marketplace dashboard credentials into public metadata.
Tools
GateCheck currently exposes six MCP tools:
boundary_guard_checkscan_x402_resourceprobe_x402_paid_pathcheck_agent_tool_readinessgenerate_x402_launch_packgenerate_trust_receipt
Public tools/list is available so buyers, agents, and directories can inspect the tool inventory before protected calls.
Buy through PayanAgent
These fixed-price offers settle in USDC through PayanAgent and automatically return the purchased GateCheck artifact:
- Quick x402 readiness check — $0.01 launch price
- Single-route launch pack — $9
- Service launch pack — $29
- Premium marketplace launch pack — $49
Buyer input is validated before PayanAgent presents the payment flow. Generated launch packs contain listing and approval-review artifacts; they do not publish listings, contact buyers, or claim marketplace endorsement.
What GateCheck Checks
- Product-scoped discovery: homepage,
llms.txt,agents.txt, product card, skill card, sitemap, and MCP server card. - MCP inventory: public initialize and tool-list introspection.
- x402 behavior: unpaid
402challenge metadata without submitting payment signatures or moving funds. - Listing readiness: buyer-facing copy, prices, evidence links, launch-pack artifacts, and claim boundaries.
Claim Boundary
GateCheck reports and receipts prove observed public metadata, unpaid 402 behavior, request summaries, hashes, and returned artifacts only.
They do not prove marketplace endorsement, settlement, security certification, custody, KYC/AML coverage, buyer adoption, or downstream execution.
Product Boundary
GateCheck is separate from Signal Desk and ResultRail.
This repository is the public distribution and marketplace-submission surface for GateCheck only.
Current Public Visibility
Verified public surfaces include:
- GateCheck remote MCP endpoint:
https://proofbeforepay.vercel.app/gatecheck/mcp - Official MCP Registry:
https://registry.modelcontextprotocol.io/v0.1/servers?search=io.github.LarryLemonBot/gatecheck - Smithery:
https://smithery.ai/servers/larrybuildsai/gatecheck - Glama:
https://glama.ai/mcp/connectors/io.github.LarryLemonBot/gatecheck - mcpservers.org:
https://mcpservers.org/servers/x402-resource-scanner-vercel-app-gatecheck-marketplaces
Known external blockers: the former MCP.so listing URL currently returns 404, and https://xpay.tools/agents.txt has not exposed gatecheck. Neither surface is claimed as live.
Marketplace Packet
- Cline submission draft:
marketplaces/cline-submission.md - MCP.Directory submission draft:
marketplaces/mcp-directory-submission.md - Server manifest:
server.json - Public scorecard:
scorecard.md - Logo SVG:
assets/gatecheck-logo.svg - Logo PNG:
assets/gatecheck-logo.png
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