Pay-per-call premium API access on Base via x402 — $0.02/request in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" via the x402 payment protocol. It is one of many endpoints offered by the lowpaymentfee.com platform, which hosts a catalog of pay-per-request APIs spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities. All endpoints are priced at $0.02 per request, payable in USDC on the Base network with no API keys, rate limits, or commitments required.
The specific endpoint `/api/v1/payments/319` is labeled "Premium API Access" in the x402 challenge but its exact functionality is not documented beyond that label. The x402 challenge confirms it is live, accepts POST requests, and requires a maximum payment of 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) on Base (asset contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913). The payment timeout is 300 seconds.
The broader platform lists endpoints for metrics, reports, data export, insights, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation — all at the same $0.02 price point. However, documentation pages (docs, pricing, README) returned only a "Connect wallet" prompt with no further technical detail, so the actual request/response schemas for this or any endpoint are unknown.
Capabilities
Use cases
- —Accessing premium API functionality with per-request USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Programmatic pay-as-you-go access to undocumented premium services
Fit
Best for
- —Developers wanting zero-commitment, keyless API access
- —AI agents that can settle x402 payments in USDC on Base
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation or guaranteed SLAs before paying
- —Anyone without a Base-compatible USDC wallet
- —High-volume use cases where per-request pricing may be inefficient
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/319 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming pricing and network. However, the actual functionality behind "Premium API Access" is completely undocumented — no request schema, no response schema, no docs beyond a wallet-connect prompt. This is effectively a stub listing.
Warnings
- —The exact functionality of /api/v1/payments/319 ('Premium API Access') is not documented anywhere in the crawled material.
- —All documentation pages (docs, pricing, README, api) returned only 'Connect wallet' with no technical content.
- —No OpenAPI spec, no request/response schema, and no usage examples are available.
- —The endpoint path '/api/v1/payments/319' with a numeric ID suggests it may be a dynamically generated or user-specific resource rather than a general-purpose API.
Citations
- —Endpoint returns 402 with x402 challenge requiring 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/payments/319
- —Platform lists APIs across data & analytics, AI & ML, finance & Web3, and infrastructure at $0.02/requesthttps://lowpaymentfee.com
- —No API keys, no rate limits, instant access, Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/payments/319