x402-gated Premium API Access on Base, pay $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" behind an x402 paywall on the Base network. The specific resource path is `/api/v1/charges/292`, which is one of many endpoints offered by the provider. The site advertises a broad catalog of pay-per-call APIs spanning data & analytics, AI & machine learning (sentiment analysis, summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation).
The endpoint accepts HTTP POST requests and returns `application/json`. Payment is settled on-chain via USDC on Base (contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`). The x402 challenge specifies a `maxAmountRequired` of 20,000 base units; since USDC uses 6 decimals, this equals $0.02 per request — consistent with the site's advertised flat pricing of $0.02/request across all endpoints. No API keys are required; access is granted purely through the x402 payment header. The provider claims no rate limits and instant access.
However, the specific functionality behind `/api/v1/charges/292` is not documented beyond the generic label "Premium API Access." The crawled docs, pricing, and README pages all returned only a "Connect wallet" prompt with no additional technical documentation, request/response schemas, or usage examples. Without knowing what this particular charge endpoint does — or what request body it expects — callers will need to experiment or contact the provider. The lack of OpenAPI specs, detailed docs, or example payloads significantly limits discoverability.
Capabilities
Use cases
- —Paying per-call for API access without needing API keys or subscriptions
- —Integrating on-chain USDC micropayments into automated agent workflows
- —Accessing a variety of data, AI, finance, and utility endpoints at low cost
Fit
Best for
- —Agents or developers who want keyless, pay-per-use API access
- —Crypto-native workflows that can settle USDC on Base
- —Low-volume or sporadic API consumers who prefer no commitments
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Developers without a Base-compatible wallet or USDC holdings
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/292 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI schema, no request/response examples, and the specific functionality of /api/v1/charges/292 is unknown beyond the generic label 'Premium API Access'. Docs pages returned only wallet-connect prompts.
Warnings
- —The specific functionality of /api/v1/charges/292 is undocumented — 'Premium API Access' is a generic label with no details on what data or service is returned.
- —No OpenAPI spec, request schema, or response schema is available.
- —All documentation pages (docs, pricing, README, api) returned only a 'Connect wallet' prompt with no usable content.
- —The provider lists many endpoint categories (AI, finance, data, utilities) but it is unclear which, if any, are fully implemented behind this charge path.
Citations
- —Flat pricing of $0.02 per request across all endpoints, no API keys, no rate limitshttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/charges/292
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/charges/292
- —Provider advertises categories: Data & Analytics, AI & ML, Finance & Web3, Infrastructurehttps://lowpaymentfee.com