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 92) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) with a maximum cost of 20,000 base units, which equals $0.02 per request (USDC uses 6 decimals).
The provider lowpaymentfee.com hosts a broader suite of x402-gated APIs spanning data & analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request with no API keys, no rate limits, and no minimum commitments. However, the specific endpoint being listed here — `/api/v1/emails/92/attachments` — is not mentioned on the provider's landing page, and no documentation describes its request or response schema.
Because there is no OpenAPI spec, no request/response examples, and no documentation beyond the generic landing page, the actual behavior of this endpoint is unclear. The x402 challenge is live and well-formed, confirming the endpoint is operational, but what data it returns (attachment metadata, binary content, etc.) and what POST body it expects remain unknown.
Capabilities
Use cases
- —Programmatically retrieving email attachments via a pay-per-request model
- —Agent-driven workflows that need to fetch specific email attachment data
- —Integrating email attachment retrieval into automated pipelines without API keys
Fit
Best for
- —Agents needing on-demand email attachment access without subscription
- —Workflows requiring x402-compatible micropayment endpoints on Base
- —Low-volume, pay-as-you-go email data retrieval
Not for
- —Bulk email processing or high-volume attachment downloads (no documented batch support)
- —Users who need detailed API documentation or guaranteed SLAs
- —Accessing arbitrary emails — this endpoint is scoped to email ID 92
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/92/attachments \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint exists and accepts payment on Base in USDC at $0.02. However, there is no OpenAPI spec, no request/response schema, no documentation for this specific endpoint, and the endpoint path (emails/92/attachments) is not listed on the provider's own landing page. Effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available for this endpoint
- —The endpoint /api/v1/emails/92/attachments is not listed on the provider's landing page — it may be an internal or unlisted resource
- —No request body schema or response schema documented; behavior is unknown
- —Docs, API, pricing, and README pages all returned only 'Connect wallet' with no useful content
- —Endpoint is scoped to a single email ID (92) — unclear if other IDs are supported
Citations
- —x402 challenge returns 402 with USDC on Base, maxAmountRequired 20000 (=$0.02)https://lowpaymentfee.com/api/v1/emails/92/attachments
- —Provider lists all APIs at $0.02/request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/emails/92/attachments