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/50/attachments

What it does

This endpoint at lowpaymentfee.com provides access to email attachments (specifically for email ID 50) 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), with no API keys, rate limits, or subscriptions required.

The provider lowpaymentfee.com hosts a broader suite of x402-gated APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/crypto market data, and infrastructure utilities — all priced at $0.02 per request. However, this specific listing covers only the `/api/v1/emails/50/attachments` endpoint. Documentation beyond the landing page is extremely sparse: the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail.

Because there is no OpenAPI schema, no request/response examples, and no documentation describing what fields to send or what the response looks like, the actual behavior of this endpoint is largely unknown. The endpoint is confirmed live (returns a valid x402 402 challenge), but callers will need to experiment to discover the expected request body and response format.

Capabilities

x402-paymentusdc-baseemail-attachmentsmicropaymentno-api-keypay-per-request

Use cases

  • —Retrieving attachments from a specific email via programmatic API call
  • —Agent-driven email attachment fetching with per-request crypto payment
  • —Integrating email attachment access into automated workflows without API key management

Fit

Best for

  • —Agents or bots that need on-demand email attachment retrieval with no signup
  • —Developers experimenting with x402 micropayment protocols
  • —Workflows requiring keyless, pay-per-use API access on Base

Not for

  • —Bulk email processing or mailbox-level access
  • —Users who need detailed API documentation or guaranteed SLAs
  • —Non-crypto users who cannot pay in USDC on Base

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/emails/50/attachments \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402_payment_token>" \
  -d '{}'

Endpoint

URLhttps://lowpaymentfee.com/api/v1/emails/50/attachments
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The endpoint is live and returns a valid x402 402 challenge, confirming it exists and accepts USDC on Base. However, there is no OpenAPI schema, no request/response examples, and no meaningful documentation — the docs/pricing/README pages are all blank beyond a wallet connect prompt. The endpoint path suggests a hardcoded email ID (50), which raises questions about generality. Effectively a stub listing.

Warnings

  • —No API documentation available — docs, pricing, and README pages are empty
  • —No request or response schema provided; callers must discover the interface experimentally
  • —Endpoint path is hardcoded to email ID 50; unclear if other email IDs are supported
  • —Provider site offers many endpoints but none have documented schemas

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-21 19:16:47Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-22

Agent access

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