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 commitments required.
The specific endpoint `/api/v1/charges/297` is labeled "Premium API Access" in the x402 challenge. The challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals), which equals $0.02 — consistent with the site's published pricing. Payment is via the x402 "exact" scheme, with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
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, and no examples available. It is unclear what specific data or functionality this particular charge endpoint (297) returns, as the site lists many different API categories but does not map charge IDs to specific services. Agents should treat this as a generic paid endpoint until more documentation surfaces.
Capabilities
Use cases
- —Paying per-call for API access without needing API keys or subscriptions
- —Programmatic agent access to paid endpoints using x402 USDC micropayments on Base
- —Integrating low-cost pay-as-you-go API calls into automated workflows
Fit
Best for
- —Agents or developers who want keyless, pay-per-request API access
- —Users who prefer crypto micropayments (USDC on Base) over traditional billing
- —Low-volume or sporadic API consumers who don't want subscriptions
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume consumers who would benefit from bulk pricing or rate-limited plans
- —Users who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/297 \
-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 request/response schema, no documentation beyond a wallet-connect prompt, and no clarity on what this specific charge ID (297) actually returns. Effectively a stub listing.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet'
- —No OpenAPI or schema describing request parameters or response format
- —Unclear what specific service charge ID 297 maps to among the many listed API categories
- —No example requests or responses available
Citations
- —The site lists APIs across data & analytics, AI & ML, finance & Web3, and infrastructure, all priced at $0.02/requesthttps://lowpaymentfee.com
- —Pricing is $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge shows maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, equaling $0.02https://lowpaymentfee.com/api/v1/charges/297