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 96) behind an x402 paywall. It accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) with a maximum cost of 20,000 base units, which equals $0.02 per request (USDC uses 6 decimals).
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 with no API keys, no rate limits, and no minimum commitments. However, the specific endpoint cataloged here (/api/v1/emails/96/attachments) is not listed on the provider's landing page among the advertised API categories, so its exact functionality and response schema are unclear.
The x402 challenge is live and well-formed (version 1, scheme "exact", 300-second timeout). No OpenAPI spec, detailed documentation, or example responses were found during crawling — the docs, pricing, and README pages all returned only a wallet-connect prompt with no substantive content. Because of this, the actual behavior of this endpoint (what attachments it returns, expected POST body, response format) remains undocumented and must be discovered by the caller.
Capabilities
Use cases
- —Programmatically retrieving email attachments behind a paywall
- —Agent-driven access to stored email data with per-request micropayments
- —Integrating x402-compatible payment flows for document retrieval
Fit
Best for
- —Agents that need to fetch email attachments without API key management
- —Developers experimenting with x402 micropayment protocols on Base
- —Automated workflows requiring pay-per-use document access
Not for
- —Bulk email processing (no documented batch endpoint or rate optimization)
- —Users who need detailed API documentation or guaranteed SLAs
- —Accessing emails other than ID 96 (only this specific resource is cataloged)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/96/attachments \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI spec, no documentation, no example request/response, and this specific endpoint is not listed among the provider's advertised APIs. The docs pages returned only wallet-connect prompts with no content.
Warnings
- —This specific endpoint (/api/v1/emails/96/attachments) is not listed among the provider's advertised APIs on the landing page — its purpose and data are unclear.
- —No documentation, OpenAPI schema, or example responses are available; the docs/pricing/README pages are empty.
- —The endpoint appears to serve a single hardcoded email (ID 96); generalizability to other email IDs is unknown.
- —Request body schema is undocumented — callers must discover expected POST parameters by trial.
Citations
- —x402 challenge returns 402 with maxAmountRequired 20000 in USDC on Base networkhttps://lowpaymentfee.com/api/v1/emails/96/attachments
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/emails/96/attachments
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —This specific email attachments endpoint is not listed among the provider's advertised API categorieshttps://lowpaymentfee.com