Sell a Paid MCP/API Call with x402 + Pyrimid

This guide shows a reproducible no-spend flow for exposing a paid MCP/API product through Pyrimid: catalog metadata, HTTP 402 payment requirements, Base USDC settlement metadata, and affiliate-aware retry headers.

Productmcp-server-audit
NetworkBase / USDC / x402
Affiliate headerX-Affiliate-ID

Catalog metadata

Query the live catalog: catalog endpoint. 

{
  "vendor_id": "pyrimid-growth",
  "product_id": "mcp-server-audit",
  "price_display": "$0.10",
  "affiliate_bps": 4000,
  "network": "base",
  "asset": "USDC",
  "endpoint": "https://pyrimid.ai/api/v1/paid/mcp-server-audit?url=https://example.com/mcp"
}

HTTP 402 before payment

curl -i "https://pyrimid.ai/api/v1/paid/mcp-server-audit?url=https://example.com/mcp"

The endpoint returns HTTP 402 with `accepts[]` metadata containing `network`, `asset`, `payTo`, `resource`, `vendorId`, `productId`, and `affiliateBps`.

Retry after payment

curl "https://pyrimid.ai/api/v1/paid/mcp-server-audit?url=https://example.com/mcp" \
  -H "X-PAYMENT: <x402-payment-proof>" \
  -H "X-Affiliate-ID: qingfeng-pyrimid-guide"

Verification

Run npm run check in the source repo to verify the live catalog and 402 response.

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