Pay-per-request email data endpoint on Base via x402, settled in USDC at $0.02/call.
What it does
This x402-enabled endpoint at `/api/v1/emails/31` is part of the lowpaymentfee.com platform, which offers a collection of pay-per-request APIs spanning data & analytics, AI/ML, finance, infrastructure, and more. Each call is settled on the Base network using USDC with no API keys, no rate limits, and no subscriptions — just a per-request micropayment of $0.02.
The specific endpoint probed (`/api/v1/emails/31`) is labeled "Premium API Access" and accepts POST requests. The x402 challenge confirms it is live, requesting a maximum of 20,000 base units of USDC (i.e., $0.02) per call on Base mainnet, paid to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3`. The response MIME type is `application/json`. However, the exact functionality of this particular email endpoint is not documented in the crawled material — the site's landing page lists categories like analytics, AI, finance, and utilities but does not mention an emails API. No OpenAPI schema, request/response examples, or detailed documentation were found for this endpoint.
Because the endpoint's actual behavior (what it returns for a given email ID, what input it expects) is undocumented in the available material, agents should treat this as a partially-described resource. The platform's broader value proposition — low-cost, keyless, instant-access APIs settled via x402 on Base — is clear, but the specifics of this email endpoint remain opaque.
Capabilities
Use cases
- —Retrieving email-related data on a per-request payment basis without API keys
- —Integrating low-cost email data lookups into agent workflows via x402
- —Programmatic access to email records settled in USDC on Base
Fit
Best for
- —Agents needing keyless, pay-per-use email data access
- —Developers prototyping with x402 micropayments on Base
- —Workflows requiring no subscription or rate-limit constraints
Not for
- —Use cases requiring documented request/response schemas before integration
- —High-volume email operations where per-call pricing is inefficient
- —Users who need non-crypto payment rails
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/31 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI schema, no request/response examples, and the specific purpose of the /api/v1/emails/31 endpoint is not explained anywhere in the crawled material. This is effectively a stub listing.
Warnings
- —No documentation found for the /api/v1/emails/31 endpoint — its purpose and expected input/output are unknown
- —The site's landing page does not list any email-related APIs, so this endpoint may be unlisted or experimental
- —No OpenAPI spec, request schema, or response examples are available
- —Docs, pricing, API, and README pages all returned only 'Connect wallet' with no substantive content
Citations
- —The endpoint returns a 402 challenge requesting 20,000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/emails/31
- —The platform advertises $0.02 per request with no API keys, no rate limits, and instant access on Basehttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/emails/31