Retrieve email attachments via x402 micropayment on Base (USDC, $0.02/request).
What it does
This endpoint at lowpaymentfee.com provides access to email attachments (specifically email ID 32) behind an x402 paywall. It accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) with an exact-scheme micropayment of $0.02 per request (20,000 base units at 6 decimals).
The provider, lowpaymentfee.com, hosts a broader suite of x402-gated APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per call. This specific endpoint (/api/v1/emails/32/attachments) is not prominently listed on the landing page, so its exact response schema and the nature of the attachments it returns are unclear. No OpenAPI spec, detailed documentation, or example responses were found during crawling; the docs, pricing, and API pages all rendered only a "Connect wallet" prompt.
The endpoint is confirmed live: it returns a proper x402 version-1 challenge with a 402 status code. There are no API keys or rate limits advertised. The payment timeout is 300 seconds. Because the endpoint path references a hardcoded email ID (32), it is unclear whether this is a demonstration/sample resource or a production endpoint serving real email data.
Capabilities
Use cases
- —Programmatically retrieving email attachments without traditional API key registration
- —Agent-driven workflows that need to fetch email attachment data with per-call payment
- —Demonstrating x402 micropayment integration on the Base network
Fit
Best for
- —Developers experimenting with x402 payment protocols
- —AI agents that need on-demand email attachment retrieval
- —Use cases requiring keyless, pay-per-use API access
Not for
- —Bulk email processing (hardcoded email ID, no batch endpoint visible)
- —Users who need detailed documentation or guaranteed SLAs
- —Applications requiring non-crypto payment methods
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/32/attachments \
-H "X-PAYMENT: <x402_payment_token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no OpenAPI spec, no documentation, no example request/response, and the endpoint path references a hardcoded email ID with no explanation. The crawled docs/pricing/API pages all rendered only 'Connect wallet' with no useful content.
Warnings
- —No OpenAPI or schema documentation available for this endpoint
- —Endpoint references a hardcoded email ID (32) — unclear if this is a demo or production resource
- —The /docs, /pricing, and /api pages returned no meaningful content beyond 'Connect wallet'
- —This endpoint is not listed among the provider's advertised APIs on the landing page
- —Response format and attachment content are entirely unknown
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/emails/32/attachments
- —The provider advertises $0.02 per request, no API keys, no rate limits, Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/emails/32/attachments