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 site advertises a broad catalog of pay-per-call APIs spanning data & analytics, 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 endpoints are priced at $0.02 per request, settled in USDC on Base with no API keys, no rate limits, and no commitments required.
The specific endpoint `/api/v1/charges/164` is labeled "Premium API Access" in the x402 challenge. The challenge confirms it accepts an exact-scheme payment of up to 20,000 base units of USDC (0x8335…) on Base, which equals $0.02 (USDC uses 6 decimals). Payment is made via the X-PAYMENT header per the x402 protocol, and the endpoint accepts POST requests returning application/json.
Documentation is extremely sparse — the /docs, /pricing, /api, 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 examples of what this particular endpoint returns. The site's landing page lists many endpoints but provides no detail on request parameters or response formats for any of them. Without documentation it is unclear what specific functionality `/api/v1/charges/164` provides beyond the generic "Premium API Access" label.
Capabilities
Use cases
- —Programmatic access to premium API functionality with per-request USDC micropayments
- —Agent-driven API consumption without pre-registration or API key management
- —Integrating pay-as-you-go API calls into Web3 workflows on Base
Fit
Best for
- —Developers wanting zero-signup, pay-per-call API access
- —AI agents that can settle x402 payments autonomously on Base
- —Projects needing low-friction API access without rate limits or subscriptions
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume consumers who prefer flat-rate or subscription pricing
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/164 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI spec, no documentation beyond a landing page listing, no request/response schemas, and no examples. The specific purpose of /api/v1/charges/164 is unclear beyond the generic 'Premium API Access' label. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README pages all show only 'Connect wallet' with no content
- —No OpenAPI or schema definition found for any endpoint
- —The specific functionality of /api/v1/charges/164 is undocumented; 'Premium API Access' is a generic label
- —Cannot verify what data or service this endpoint actually returns without paying
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/charges/164
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The site lists APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/charges/164