x402-gated email API endpoint on Base, pay $0.02 per request in USDC with no API keys.
What it does
This endpoint at lowpaymentfee.com provides a premium email-related API accessible via the x402 payment protocol. The specific resource `/api/v1/emails/6` is part of a broader platform that offers dozens of pay-per-call endpoints spanning data analytics, AI/ML inference, finance, crypto, and utility services — all priced at $0.02 per request and settled in USDC on the Base network.
The endpoint accepts HTTP POST requests and returns JSON. Payment is handled inline via the x402 protocol: callers attach an `X-PAYMENT` header containing a signed USDC payment of up to 20,000 base units ($0.02, since USDC uses 6 decimals) to the provider's address on Base. No API keys, rate limits, or upfront commitments are required — each call is independently paid for at the moment of use.
The exact functionality of the `/api/v1/emails/6` resource is not documented in the available crawl material. The provider's landing page lists categories like Data & Analytics, AI & ML, Finance & Web3, and Infrastructure, but does not enumerate email-specific endpoints. The description field in the x402 challenge simply reads "Premium API Access," offering no further detail on what this particular endpoint returns or expects as input. Prospective callers should test the endpoint or seek additional documentation before relying on it in production.
Capabilities
Use cases
- —Retrieving email-related data on a per-request payment basis without needing an API key
- —Integrating a pay-as-you-go email service into an AI agent workflow via x402
- —Testing x402 protocol integrations with a low-cost endpoint on Base
Fit
Best for
- —Developers experimenting with x402 payment-gated APIs
- —Agents that need on-demand email functionality without subscription overhead
- —Low-volume or bursty workloads where per-call pricing is preferable
Not for
- —High-volume email sending or transactional email at scale (no documented throughput guarantees)
- —Users who need detailed API documentation or SLA commitments before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/6 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <signed-x402-payment-header>"Endpoint
Quality
The endpoint is live (returns a valid 402 x402 challenge), but there is no documentation on what /api/v1/emails/6 actually does, no request/response schema, no examples, and the crawled pages beyond the landing page are empty ('Connect wallet'). The listing is effectively a stub with only pricing and protocol details confirmed.
Warnings
- —The exact purpose and input/output schema of /api/v1/emails/6 are undocumented; the description is only 'Premium API Access'.
- —No OpenAPI spec, no request body schema, and no response examples are available.
- —Crawled documentation, pricing, API, and README pages returned no useful content (only 'Connect wallet').
- —The /api/v1/emails/ path does not appear in the provider's own landing page endpoint listing, raising questions about whether this is a current or deprecated resource.
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/emails/6
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/emails/6
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Basehttps://lowpaymentfee.com
- —The provider lists categories including Data & Analytics, AI & ML, Finance & Web3, and Infrastructure but does not list email endpoints on the landing pagehttps://lowpaymentfee.com