Paid Agent APIs — Storefront Grader & GEO Audit

Two pay-per-call APIs built for AI agents. No accounts, no API keys, no subscriptions — payment is the auth. Each call is paywalled with the x402 protocol: send a request, get an HTTP 402 with payment requirements, pay in USDC on Base, get the result.

Operated by Harrison Truong · Contact: theharrisontruong@gmail.com

---

1. AI Storefront Readiness Grader — $1.00 / call

Grades any storefront URL A–F across 20 weighted conversion-readiness checks (checkout friction, trust signals, mobile readiness, page performance basics, merchandising completeness, and more) and returns the grade plus the failing checks.

HTTP endpoint	POST https://grader-al6bxcngia-ue.a.run.app/grade
MCP endpoint	POST https://grader-al6bxcngia-ue.a.run.app/mcp
MCP tool	grade_storefront
Input	{ "url": "https://your-store.example" }
Price	$1.00 per call (USDC, Base mainnet)
Directory listing	https://www.x402scan.com/server/47e39cb6-7143-4052-b4b1-4dac0e1a2b40

2. GEO Audit — $1.50 / call

Scores any URL's visibility to AI search engines (ChatGPT, Perplexity, Claude, Google AI Overviews) across 20 weighted checks — crawlability for AI bots, structured data, content extractability, entity signals — and returns the score plus concrete fixes.

HTTP endpoint	POST https://geo-al6bxcngia-ue.a.run.app/geo
MCP endpoint	POST https://geo-al6bxcngia-ue.a.run.app/mcp
MCP tool	audit_geo
Input	{ "url": "https://your-site.example" }
Price	$1.50 per call (USDC, Base mainnet)
Free tier	POST https://geo-al6bxcngia-ue.a.run.app/geo-lite — tool audit_geo_lite, free, rate-limited to 20/hour

---

Payment terms (x402)

• Protocol: x402 (HTTP 402 Payment Required), exact scheme
• Network: Base mainnet (eip155:8453)
• Asset: USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913)
• Pay to: 0xd702C8A8Ee30F6950A2a663010d12FC195D5348e
• Facilitator: PayAI (https://facilitator.payai.network)
• Discovery: both services serve a discovery document at /.well-known/x402 and declare the Bazaar discovery extension (extensions.bazaar) in their 402 responses.

Any x402-aware client works out of the box (@x402/fetch, x402 Python package, CDP or PayAI client wrappers). Unpaid requests receive a standard 402 challenge with the full payment requirements — no signup needed to inspect them:

curl -i -X POST https://grader-al6bxcngia-ue.a.run.app/grade \
  -H 'Content-Type: application/json' \
  -d '{"url": "https://example.com"}'
# → HTTP 402 with payment requirements (1.00 USDC, Base mainnet)

Run a paid call from code (buyer example)

examples/buy-with-x402/ is a runnable Node script that buys a call end-to-end with @x402/fetch. It defaults to a dry run: it sends one unpaid request, prints the decoded 402 challenge, and exits — it only pays when you pass --pay with your own wallet key in EVM_PRIVATE_KEY.

node examples/buy-with-x402/buy.mjs            # dry run, prints the 402
node examples/buy-with-x402/buy.mjs geo https://your-site.example

MCP usage

Both services expose a stateless streamable-HTTP MCP endpoint at /mcp on their base URLs. Add either to any MCP client as a remote server:

{
  "mcpServers": {
    "storefront-grader": { "url": "https://grader-al6bxcngia-ue.a.run.app/mcp" },
    "geo-audit": { "url": "https://geo-al6bxcngia-ue.a.run.app/mcp" }
  }
}

Tool calls return an in-protocol 402 until the client pays via x402; the free audit_geo_lite tool on the GEO server works without payment.

Registry metadata in this repo

• server.json — Official MCP Registry manifest for the Storefront Grader (remote).
• server-geo.json — Official MCP Registry manifest for GEO Audit (remote).
• glama.json — Glama maintainer claim for this repository.

License

MIT — see LICENSE. The license covers this documentation/metadata repo; the hosted services themselves are pay-per-call as described above.