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 8) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (USD Coin) at a cost of $0.02 per request (20,000 base units with 6 decimals). No API keys or rate limits are required — callers simply include an X-PAYMENT header with a valid x402 payment proof.
The broader lowpaymentfee.com platform advertises a suite of pay-per-call APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/crypto data feeds, and utility services (geocoding, validation, conversion, generation). All endpoints share the same $0.02/request pricing model and x402 payment protocol on Base. However, this specific listing covers only the `/api/v1/emails/8/attachments` endpoint, whose exact response schema and attachment content are not documented in the available crawl material.
The endpoint is live and returns a proper x402 challenge (HTTP 402) when called without payment. The x402 challenge specifies version 1, the "exact" payment scheme, a 300-second timeout, and payment to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 using the USDC contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base.
Capabilities
Use cases
- —Programmatically retrieving email attachments without traditional API key management
- —Agent-driven workflows that need to fetch email content with per-call micropayments
- —Automated document retrieval from email systems via crypto-settled API calls
Fit
Best for
- —Agents or bots that need on-demand email attachment access with no subscription
- —Developers experimenting with x402 pay-per-call patterns on Base
- —Low-volume, ad-hoc retrieval of specific email attachments
Not for
- —Bulk email processing or high-volume attachment downloads (no batch endpoint documented)
- —Users who need access to arbitrary email IDs (this endpoint is scoped to email 8)
- —Non-crypto users who cannot settle payments on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/8/attachments \
-H "X-PAYMENT: <x402-payment-proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation on request body format, response schema, or what the email attachments actually contain. The crawl pages beyond the homepage returned only 'Connect wallet' with no useful content. The endpoint path suggests a very specific resource (email 8) with unclear general utility.
Warnings
- —No documentation available for this specific endpoint — request body and response schema are unknown
- —Endpoint is scoped to a single email ID (8); unclear if other email IDs are accessible
- —The broader platform docs, pricing, and API pages returned no meaningful content ('Connect wallet' only)
- —The nature and content of the email attachments is completely undocumented
Citations
- —Endpoint returns HTTP 402 with x402 challenge on Base using USDC at maxAmountRequired 20000 (=$0.02)https://lowpaymentfee.com/api/v1/emails/8/attachments
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/emails/8/attachments