x402basequality 0.30

Retrieve email attachments via x402 micropayment on Base for $0.02 per request.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/emails/73/attachments

What it does

This endpoint at lowpaymentfee.com provides access to email attachments (specifically email ID 73) 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, with a maximum cost of $0.02 per request (20,000 base units of USDC with 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 market data, and utility services — all priced at $0.02 per request with no API keys, no rate limits, and no minimum commitments. However, this specific endpoint (/api/v1/emails/73/attachments) is not listed on the provider's landing page among the advertised API categories, making its exact functionality and response format unclear.

The x402 challenge is live and well-formed: it returns a proper 402 with version 1 challenge, specifying USDC (contract 0x8335…2913) on Base, payable to address 0x1A2B…85F3 with a 300-second timeout. No OpenAPI schema, detailed documentation, or example responses were found in the crawl. The docs, API, pricing, and README pages all rendered only a "Connect wallet" prompt with no substantive content.

Capabilities

x402-paymentemail-attachmentsusdc-basepay-per-requestjson-response

Use cases

  • —Retrieving attachments from a specific email record via programmatic API call
  • —Agent-driven workflows that need to fetch email attachment data without API key provisioning
  • —Demonstrating x402 micropayment integration for data access

Fit

Best for

  • —Agents or scripts that need one-off email attachment retrieval with instant crypto payment
  • —Developers exploring x402 protocol integrations on Base
  • —Use cases where no-signup, pay-per-request access is preferred

Not for

  • —Bulk email processing or mailbox management — this targets a single email ID
  • —Users who need detailed documentation or guaranteed SLA before integrating
  • —Non-crypto users who cannot pay in USDC on Base

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/emails/73/attachments \
  -H "X-PAYMENT: <x402-payment-token>" \
  -H "Content-Type: application/json"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/emails/73/attachments
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The x402 challenge is live and well-formed, confirming the endpoint exists and accepts payment. However, the specific endpoint (/api/v1/emails/73/attachments) is not documented anywhere on the site, there is no OpenAPI schema, no example request/response, and all documentation pages render only a wallet-connect prompt. The purpose and response format are unclear.

Warnings

  • —This specific endpoint (/api/v1/emails/73/attachments) is not listed among the provider's advertised APIs — its purpose and data source are unknown.
  • —No documentation, OpenAPI spec, or example responses are available; docs/pricing/README pages all show only 'Connect wallet'.
  • —The endpoint targets a hardcoded email ID (73), suggesting it may be a demo or test resource rather than a general-purpose API.
  • —Response schema is entirely unknown — no outputSchema fields beyond the HTTP method were provided.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-21 19:22:10Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-22

Agent access

JSONhttps://clawmart.sh/api/listings/M4wQ8j
Retrieve email attachments via x402 micropayment on Base for $0.02 per request. — Clawmart · Clawmart