Retrieve email attachments via x402 micropayment on Base for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com provides access to email attachments (specifically for email ID 2) behind an x402 paywall. It accepts POST requests and returns JSON. Payment is settled in USDC on the Base network using the x402 "exact" scheme.
The endpoint is part of a broader platform (lowpaymentfee.com) that offers a variety of pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and utility services — all priced at $0.02 per request. The platform advertises no API keys, no rate limits, and instant access; callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The specific functionality of this endpoint — retrieving attachments for email ID 2 — is narrowly scoped and not well-documented. There is no OpenAPI schema, no request/response examples, and no documentation beyond the generic landing page. The x402 challenge confirms the endpoint is live and accepts payments of up to 20,000 base units of USDC (6 decimals → $0.02) to wallet 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 on Base. However, what constitutes a valid POST body and what the response payload looks like remain unknown.
Capabilities
Use cases
- —Programmatically retrieving email attachments without traditional API key authentication
- —Agent-driven workflows that need to fetch email file attachments on demand
- —Demonstrating x402 micropayment integration for email data access
Fit
Best for
- —Developers experimenting with x402 payment protocols
- —Agents that need one-off email attachment retrieval via crypto micropayments
- —Use cases where avoiding API key management is desirable
Not for
- —Bulk email processing or mailbox management — this targets a single email ID
- —Users who need well-documented, production-grade email APIs with full schema coverage
- —Non-crypto workflows that require traditional billing
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/2/attachments \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_proof>"Endpoint
Quality
The x402 challenge confirms the endpoint is live and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response examples, no documentation for this specific endpoint, and the use case (attachments for a hardcoded email ID 2) is unclear and narrow. Docs pages returned only 'Connect wallet' with no content.
Warnings
- —No documentation available for this specific endpoint — all doc/pricing/API pages return only 'Connect wallet'
- —The endpoint targets a hardcoded email ID (2); unclear if this is a demo or production resource
- —No request body schema or response schema provided
- —No OpenAPI or AI plugin manifest found
- —Actual functionality behind the paywall is unverified
Citations
- —The endpoint returns a 402 challenge with x402Version 1, accepting USDC on Base with maxAmountRequired of 20000 base units ($0.02)https://lowpaymentfee.com/api/v1/emails/2/attachments
- —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/2/attachments