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 30) behind an x402 paywall. It accepts POST requests and returns JSON. Payment is settled in USDC on the Base network at $0.02 per call (maxAmountRequired of 20,000 base units with 6 decimals = $0.02).
The endpoint is part of a broader platform (lowpaymentfee.com) that offers a variety of x402-gated APIs spanning data & analytics, AI/ML inference, finance & Web3 data, and infrastructure utilities — 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.
Documentation is extremely sparse. The crawled /docs, /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema documentation, and no examples available. The specific functionality of this email-attachments endpoint — what input it expects and what attachment data it returns — is not documented anywhere in the crawled material. The endpoint is confirmed live (402 challenge captured), but the lack of documentation makes integration difficult without experimentation.
Capabilities
Use cases
- —Retrieving email attachments programmatically with per-request micropayment
- —Agent-driven email data extraction without API key management
- —Accessing email content behind a crypto paywall
Fit
Best for
- —Agents that need on-demand email attachment retrieval without subscription
- —Developers experimenting with x402 payment-gated APIs
- —Low-volume, pay-as-you-go email data access
Not for
- —High-volume email processing requiring documented schemas and SLAs
- —Users who need comprehensive email management (send, search, organize)
- —Anyone requiring detailed API documentation before integration
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/30/attachments \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_proof>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, but there is zero documentation on request/response schemas, no OpenAPI spec, and all doc pages return only 'Connect wallet'. The specific purpose of this email-attachments endpoint is unclear beyond its URL path. This is effectively a stub listing.
Warnings
- —No API documentation available — all doc pages return only 'Connect wallet'
- —No request or response schema documented; input format and output structure are unknown
- —The endpoint targets a hardcoded email ID (30) with no explanation of what this represents
- —The broader platform lists many endpoints but none appear to have public documentation
- —Cannot verify what data this endpoint actually returns without making a paid request
Citations
- —Endpoint returns 402 with x402 challenge requiring USDC payment on Base networkhttps://lowpaymentfee.com/api/v1/emails/30/attachments
- —maxAmountRequired is 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913)https://lowpaymentfee.com/api/v1/emails/30/attachments
- —Platform advertises $0.02 per request, no API keys, no rate limits, instant accesshttps://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) contain only 'Connect wallet' with no substantive contenthttps://lowpaymentfee.com/docs