Pay-per-request email data endpoint on Base via x402, settled in USDC at $0.02/call.
What it does
This x402-enabled endpoint at `/api/v1/emails/72` is part of the lowpaymentfee.com platform, which offers a collection of pay-per-request APIs spanning data & analytics, AI/ML, finance, infrastructure, and more. Each call is settled on the Base network using USDC (USD Coin) at a cost of $0.02 per request (20,000 base units with 6 decimals). No API keys, rate limits, or subscriptions are required — callers simply attach an x402 payment header to each POST request.
The specific endpoint `/api/v1/emails/72` is listed under the title "Premium API Access" but its exact functionality is not documented in the crawled material. It appears to be an email-related resource (based on the URL path), but the provider's landing page does not list this particular endpoint among its advertised API categories. The response MIME type is `application/json`. The x402 challenge is live and well-formed, confirming the endpoint is operational and accepting payments.
The broader lowpaymentfee.com platform advertises endpoints across several domains including sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, geocoding, validation, and more — all at the same $0.02/request price point. Documentation beyond the landing page is extremely thin; the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no additional technical detail.
Capabilities
Use cases
- —Retrieving email-related data on a per-request payment basis without needing an API key
- —Integrating pay-as-you-go email data into agent workflows that support x402 payments
- —Accessing premium email content or metadata via crypto micropayments
Fit
Best for
- —Developers or agents that already support x402 payment flows
- —Use cases requiring no-signup, no-rate-limit API access
- —Micropayment-friendly workflows on the Base L2 network
Not for
- —Users who need detailed API documentation or schema definitions before integrating
- —High-volume use cases where per-request pricing may add up compared to subscription models
- —Anyone without a Base-network USDC wallet or x402-compatible client
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/72 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works and costs $0.02 USDC on Base. However, there is no documentation for this specific endpoint — no request/response schema, no description of what it returns, and no examples. The docs pages are empty beyond a wallet-connect prompt. The endpoint's purpose (emails/72) is unclear.
Warnings
- —The specific endpoint /api/v1/emails/72 is not listed among the provider's advertised APIs on the landing page — its exact purpose is unknown.
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no technical content.
- —No request body schema or response schema is available; integration requires trial-and-error.
- —No OpenAPI spec, ai-plugin manifest, or agents.txt found.
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 in USDC on Base networkhttps://lowpaymentfee.com/api/v1/emails/72
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/emails/72
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com