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 hosts 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 minimum commitments.
The specific endpoint `/api/v1/charges/209` is labeled "Premium API Access" and accepts POST requests. The x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913, 6 decimals), which equals $0.02 per call. Payment is made via the x402 exact scheme to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
Documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema, and no examples available. It is unclear what specific functionality the `/api/v1/charges/209` endpoint provides beyond the generic "Premium API Access" label, as the site's catalog lists many different endpoints but this particular path does not match any of the named APIs on the landing page.
Capabilities
Use cases
- —Programmatic access to premium API services without traditional API key registration
- —Agent-driven workflows that need instant, keyless API access with crypto micropayments
- —Integrating pay-per-call data or utility endpoints into Web3 applications
Fit
Best for
- —Developers wanting zero-signup, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously on Base
- —Projects needing low-cost per-request pricing without rate limits
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Applications requiring non-crypto payment methods
- —High-volume use cases where subscription pricing would be more economical
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/209 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation, no OpenAPI schema, no request/response examples, and the specific purpose of /api/v1/charges/209 is unclear. The docs pages are empty beyond a wallet-connect prompt. This is effectively a stub listing.
Warnings
- —No OpenAPI spec or schema available for this endpoint
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no technical content
- —The path /api/v1/charges/209 does not correspond to any named API in the site's catalog — its specific functionality is unknown
- —No request body schema or response schema documented anywhere
Citations
- —The site lists APIs across data & analytics, AI & ML, finance & Web3, and infrastructure categories, all priced at $0.02/requesthttps://lowpaymentfee.com
- —Pricing is $0.02 per request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge shows maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base networkhttps://lowpaymentfee.com/api/v1/charges/209