Pay-per-call premium API access on Base via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. The specific endpoint at `/api/v1/payments/205` is labeled "Premium API Access" and accepts POST requests. Payment is settled in USDC (contract 0x8335…2913 on Base) with a maximum amount of 20,000 base units, which equals $0.02 per call (USDC uses 6 decimals). No API keys, rate limits, or upfront commitments are required — each request is individually paid for via the X-PAYMENT header.
The broader lowpaymentfee.com platform advertises endpoints across four categories: Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All listed endpoints share the same $0.02/request pricing. However, the probed endpoint `/api/v1/payments/205` does not clearly map to any of these named services — its exact functionality beyond "Premium API Access" is not documented.
Documentation is extremely sparse. The /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawl. The endpoint is confirmed live (returns a valid 402 x402 challenge), but what data or service it actually returns upon successful payment is unknown.
Capabilities
Use cases
- —Programmatic access to premium API services without API key management
- —Agent-driven pay-per-call workflows settled in USDC on Base
- —Exploring x402 protocol integration for micropayment-gated endpoints
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that need keyless, pay-as-you-go API access on Base
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation or guaranteed SLAs
- —Anyone requiring non-crypto payment methods
- —Production workloads that depend on well-documented request/response contracts
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/205 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and payment details. However, documentation is essentially nonexistent — no OpenAPI spec, no request/response schemas, no examples, and the actual functionality behind 'Premium API Access' is undefined. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /api, /pricing, and /README all render only 'Connect wallet' with no content
- —The exact functionality of /api/v1/payments/205 ('Premium API Access') is not described anywhere; it does not map to any named endpoint on the homepage
- —No request body schema or response schema is documented
- —No OpenAPI or machine-readable API specification found
Citations
- —Endpoint returns a valid x402 402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/payments/205
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/payments/205
- —All listed endpoints priced at $0.02/request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform advertises endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com