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 87) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled in USDC on the Base network at $0.02 per call (maxAmountRequired of 20,000 base units with 6 decimals = $0.02), matching the site-wide flat pricing.
The broader lowpaymentfee.com platform advertises a range of x402-gated APIs spanning data & analytics, AI/ML (sentiment analysis, summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints share the same $0.02/request pricing with no API keys, no rate limits, and no minimum commitments. However, this specific listing is for the email attachments endpoint only.
Documentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available. The endpoint is confirmed live via a valid x402 402 challenge, but the actual behavior and response format of the attachments endpoint can only be guessed at from the path structure and MIME type declaration (application/json).
Capabilities
Use cases
- —Retrieving email attachments programmatically with per-call micropayments
- —Agent-driven workflows that need to fetch email data without API key provisioning
- —Automated document retrieval from email storage behind a paywall
Fit
Best for
- —Agents or bots that need one-off email attachment retrieval without subscription overhead
- —Developers experimenting with x402 payment-gated APIs
- —Low-volume, pay-as-you-go access to email data
Not for
- —High-volume email processing where per-request fees add up quickly
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —Accessing emails other than ID 87 (this endpoint is scoped to a single email)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/87/attachments \
-H "X-PAYMENT: <x402-payment-header>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live via a valid x402 402 challenge and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and the endpoint path (emails/87/attachments) is oddly specific with no explanation. The purpose and actual output are unclear.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README pages all show only 'Connect wallet'
- —No OpenAPI or schema definition; request body and response format are unknown
- —Endpoint is scoped to a single email ID (87) with no explanation of what this email contains
- —The broader platform lists many API categories but none mention email endpoints, raising questions about this endpoint's provenance
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 in USDC on Basehttps://lowpaymentfee.com/api/v1/emails/87/attachments
- —All endpoints on the platform are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/emails/87/attachments