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 72) behind an x402 paywall. Payment is settled in USDC on the Base network at $0.02 per request (maxAmountRequired of 20,000 base units with 6 decimals). The endpoint accepts POST requests and returns application/json responses.
lowpaymentfee.com is a broader platform offering a variety of x402-gated API endpoints across categories including data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all priced uniformly at $0.02 per request. The platform advertises no API keys, no rate limits, and instant access, with all payments occurring on the Base network.
The specific endpoint `/api/v1/emails/72/attachments` is not documented on the site's landing page among the listed APIs, and no schema or documentation describes the request body format or response structure for email-related endpoints. The endpoint is live (returning a valid 402 challenge), but the lack of documentation makes it difficult to determine what input is expected or what the response payload looks like. This appears to be either an unlisted endpoint or part of a broader email API not yet surfaced in the public catalog.
Capabilities
Use cases
- —Retrieving email attachments programmatically via micropayment
- —Agent-driven email data extraction with per-request billing
- —Accessing stored email content without API key management
Fit
Best for
- —Agents needing on-demand email attachment retrieval with crypto micropayments
- —Developers wanting keyless, pay-per-use email data access
- —Workflows that settle payments in USDC on Base L2
Not for
- —Bulk email processing requiring thousands of requests (no documented batch endpoint)
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Non-crypto payment workflows (only USDC on Base is accepted)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/72/attachments \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but there is no documentation, no OpenAPI schema, no request/response examples, and this specific email endpoint is not listed among the site's public APIs. The crawled docs/pricing/README pages all returned only 'Connect wallet' with no useful content.
Warnings
- —This specific endpoint (/api/v1/emails/72/attachments) is not listed among the site's publicly advertised APIs
- —No request body schema or response schema is documented anywhere
- —All documentation pages (docs, api, pricing, README) returned only 'Connect wallet' with no actual content
- —The endpoint references a hardcoded email ID (72); unclear if other IDs are available or how to discover them
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 in USDC on Base networkhttps://lowpaymentfee.com/api/v1/emails/72/attachments
- —The platform advertises $0.02 per request 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/attachments