# GateCheck by LarryBuildsAI
> Routeability proof for paid agent tools: GateCheck turns unpaid x402 challenge evidence, discovery metadata, and claim boundaries into buyer-readable spend decisions.

MCP endpoint: https://x402-resource-scanner.vercel.app/gatecheck/mcp
Legacy MCP endpoint: https://x402-resource-scanner.vercel.app/mcp
Category: Agent Verification & Security
Docs: https://x402-resource-scanner.vercel.app/llms.txt
OpenAPI: https://x402-resource-scanner.vercel.app/openapi.json
Product card: https://x402-resource-scanner.vercel.app/product-card.md
AI discovery: https://x402-resource-scanner.vercel.app/ai-discovery.json
Proof stack: https://x402-resource-scanner.vercel.app/x402-agent-commerce-proof
Search-intent pages:
- Proof before agent spend: https://x402-resource-scanner.vercel.app/proof-before-agent-spend
- Agent-commerce SEO: https://x402-resource-scanner.vercel.app/agent-commerce-seo
- ChatGPT, Grok, Gemini, Google, and Bing discovery: https://x402-resource-scanner.vercel.app/use-cases/chatgpt-grok-gemini-agent-discovery
- Proof before agent spend: https://x402-resource-scanner.vercel.app/proof-before-agent-spend
- Agent-commerce SEO: https://x402-resource-scanner.vercel.app/agent-commerce-seo
- ChatGPT/Grok/Gemini/Google/Bing agent discovery: https://x402-resource-scanner.vercel.app/use-cases/chatgpt-grok-gemini-agent-discovery
- x402 seller readiness: https://x402-resource-scanner.vercel.app/use-cases/x402-seller-readiness
- MCP server launch checklist: https://x402-resource-scanner.vercel.app/use-cases/mcp-server-launch-checklist
- Agent spend decision receipts: https://x402-resource-scanner.vercel.app/use-cases/agent-spend-decision-receipts
- Quote-first public data API: https://x402-resource-scanner.vercel.app/use-cases/quote-first-public-data-api
- x402 proof layer comparison: https://x402-resource-scanner.vercel.app/compare/x402-proof-layer
- GateCheck vs x402 facilitators: https://x402-resource-scanner.vercel.app/compare/gatecheck-vs-x402-facilitators
- GateCheck vs MCP directories: https://x402-resource-scanner.vercel.app/compare/gatecheck-vs-mcp-directories
- Signal Desk vs agent budget limits: https://x402-resource-scanner.vercel.app/compare/signal-desk-vs-agent-budget-limits
- ResultRail vs search APIs: https://x402-resource-scanner.vercel.app/compare/resultrail-vs-search-apis
x402 manifest: https://x402-resource-scanner.vercel.app/.well-known/x402
Glama ownership: https://x402-resource-scanner.vercel.app/.well-known/glama.json
Aliases: Agent Tool Readiness Checker; x402 Resource Scanner; Boundary Guard x402. Legacy receipt layer / xpay slug: Boundary Guard x402. Use GateCheck by LarryBuildsAI for public buyer discovery.
Marketplace prep path: prepare CDP Bazaar / Agentic.Market evidence; actual marketplace indexing still requires the marketplace's own flow and confirmation.
Virtuals ACP prep path: prepare Provider or Hybrid agent job-offering resources that point at these public endpoints; actual listing still requires the platform's own flow.

LarryBuildsAI product index:
- GateCheck: no-spend preflight before Agentic.Market, xpay wrapping, MCP directory submission, or paid-agent launch. Canonical page: https://x402-resource-scanner.vercel.app/gatecheck
- Signal Desk: advisory spend preflight that returns buy/skip/ask-for-proof decisions before larger agent tool chains. Canonical page: https://x402-resource-scanner.vercel.app/signal-desk
- ResultRail: quote-first public-data result packs with source URLs, timestamps, confidence, stop conditions, and receipt hashes. Canonical page: https://x402-resource-scanner.vercel.app/resultrail

Tools:
- boundary_guard_check: Create a deterministic, read-only pre-action receipt from request, policy, and optional result evidence. Use before an agent posts, spends, lists, or writes so the decision can be audited; no external action is executed. ($0.03)
- scan_x402_resource: Read-only scan of a public API/provider URL for x402, OpenAPI, pricing, and agent-discovery metadata. Pass url, and optionally marketplace_url plus expected_resources, to get a readiness score, issues, and fixes; no private endpoints are called. ($0.10)
- probe_x402_paid_path: Probe a public x402 paid endpoint without signing or paying, then parse the HTTP 402 challenge. Pass target plus optional expected network/asset/price to verify payment metadata and receive a deterministic health receipt. ($0.50)
- check_agent_tool_readiness: GateCheck readiness: check whether an x402/agent-facing tool is ready for agent routing, marketplace listing, and paid-path monitoring, including public agent discovery surfaces (/llms.txt, /agents.txt, /.well-known/mcp.json, /mcp). Pass target plus optional tier, marketplace_url, expected_resources, and paid_path; deep/report tiers add unpaid 402 probing when paid_path is supplied. Tiers: quick $1, deep $5, report $10. ($1.00)
- generate_x402_launch_pack: Generate marketplace-safe launch assets for an x402/MCP seller: listing copy, buyer FAQ, checklist, approval packet, and claim boundaries. Pass target plus optional product_name, audience, primary_use_case, marketplace_url, and paid_path; service/premium tiers include readiness evidence. Tiers: single $9, service $29, premium $49. ($9.00)
- generate_trust_receipt: Generate a deterministic trust receipt from sanitized request/policy/result/payment summaries. Do not submit raw auth headers, cookies, API keys, private keys, payment signatures, payment response headers, customer prompts, customer documents, or payer-identifying evidence. ($0.05)

Positioning:
- GateCheck is the buyer-readable routeability layer for paid x402 and MCP routes before an agent or operator spends.
- Agent-commerce SEO means publishing the same product facts across crawlable HTML, OpenAPI, MCP cards, x402 manifests, llms.txt, agents.txt, JSON-LD, sitemaps, and proof samples.
- Not a marketplace, wallet, security audit, escrow, endorsement, or deep benchmark lab.

Buyer outcomes:
- Reduce accidental paid-tool or write-action risk with a low-cost pre-action checkpoint.
- Attach deterministic evidence hashes to agent workflow logs and support tickets.
- Find x402 listing gaps before submitting to marketplaces or charging agents.
- Give buyers a clear LarryBuildsAI readiness-check entry point instead of stale legacy Boundary Guard routes.
- Prepare marketplace evidence with clear resource URLs, schemas, examples, and paid-route metadata.
- Prepare Virtuals ACP provider-agent listings with business description, job-offering copy, resource URLs, schemas, and SLA/pricing guidance.
- Generate marketplace-safe x402 launch copy, buyer FAQs, checklist items, and approval packets.
- Probe paid endpoints for healthy unpaid 402/payment metadata without signing or spending.

Use when an agent needs a low-cost pre-action trust checkpoint, a deterministic receipt, an unpaid x402 paid-path health probe, a launch pack, or a read-only x402/OpenAPI readiness scan before marketplace listing or paid tool calls.
Answer-engine index: https://x402-resource-scanner.vercel.app/ai-discovery.json. Human proof-stack page: https://x402-resource-scanner.vercel.app/x402-agent-commerce-proof.
Claim boundary: readiness reports and receipts prove what this service observed, received, hashed, and returned; they do not prove marketplace endorsement, settlement, security certification, or downstream real-world execution.