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 email ID 7) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled in USDC on the Base network using the x402 "exact" scheme, costing 20,000 base units of USDC (i.e., $0.02 per request, since USDC uses 6 decimals).
The provider lowpaymentfee.com hosts a broader suite of pay-per-call APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/crypto data feeds, and utility services — all priced at $0.02 per request with no API keys, no rate limits, and no minimum commitments. However, this specific listing covers only the `/api/v1/emails/7/attachments` endpoint. The crawled documentation pages were essentially empty (showing only a "Connect wallet" prompt), so there is no detailed schema, request/response format, or usage documentation available beyond what the x402 challenge reveals.
The endpoint is live and returns a valid x402 challenge with version 1. Payment is made to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using USDC contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` on Base, with a maximum timeout of 300 seconds.
Capabilities
Use cases
- —Retrieving email attachments programmatically with per-request micropayments
- —Agent-driven email data extraction without API key management
- —Accessing email content behind a crypto paywall on Base
Fit
Best for
- —Agents or bots 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 where per-request costs add up
- —Users who need detailed API documentation or guaranteed SLAs
- —Non-crypto users who cannot settle payments in USDC on Base
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/7/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 documentation, no request/response schema, and no examples available. The docs, pricing, API, and README pages all render only a 'Connect wallet' prompt with no usable content. The specific purpose of this email attachments endpoint is unclear beyond its URL path.
Warnings
- —No API documentation available — all doc pages show only 'Connect wallet'
- —No request or response schema provided; input/output formats are unknown
- —The endpoint targets a hardcoded email ID (7); unclear if other email IDs are accessible or what data is returned
- —Provider appears to be a generic demo/showcase site; actual data quality and reliability are unverified
Citations
- —Endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/emails/7/attachments
- —All APIs on the site are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/emails/7/attachments